Techniques for integrated access and backhaul (IAB) nodes

ABSTRACT

Various embodiments herein provide techniques for integrated access and backhaul (IAB) nodes. For example, embodiments include techniques associated with: rate-proportional routing for network coding; utilizing multiple routes in IAB networks; user equipment (UE) and parent selection for efficient topology in IAB networks; establishing efficient IAB topologies; and/or adaptive coded-forwarding for network coding. Other embodiments may be described and claimed.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims priority to U.S. Provisional PatentApplication No. 62/898,386 which was filed Sep. 10, 2019, U.S.Provisional Patent Application No. 62/908,379, which was filed Sep. 30,2019, U.S. Provisional Patent Application No. 62/909,067, which wasfiled Oct. 1, 2019, U.S. Provisional Patent Application No. 62/909,068,which was filed Oct. 1, 2019, and U.S. Provisional Patent ApplicationNo. 62/925,545, which was filed Oct. 24, 2019, the disclosures of whichare hereby incorporated by reference.

FIELD

Embodiments relate generally to the technical field of wirelesscommunications.

BACKGROUND

In integrated access and backhaul (IAB) networks, network coding can beused for enhancing network reliability and reducing delay. When multiplepaths from source to destination exists, the network coded packetsegments need to be routed to different paths. How routing is performedon these paths impacts the reliability performance and network load.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will be readily understood by the following detaileddescription in conjunction with the accompanying drawings. To facilitatethis description, like reference numerals designate like structuralelements. Embodiments are illustrated by way of example and not by wayof limitation in the figures of the accompanying drawings.

FIG. 1 schematically illustrates network encoding to exploit multi-pathdiversity, in accordance with various embodiments.

FIG. 2 illustrates an IAB network in accordance with variousembodiments.

FIG. 3 illustrates simulation results to compare packet success rate(ratio of timely received packets) of round-robin routing and arate-proportional routing scheme, in accordance with variousembodiments.

FIG. 4 illustrates an IAB network in accordance with variousembodiments.

FIG. 5 shows an example of a network architecture for IAB in which thereare multiple routes, in accordance with various embodiments.

FIG. 6 shows an example protocol architecture for RRC connectivitybetween a UE and an IAB donor in a multi-hop IAB network, in accordancewith various embodiments.

FIG. 7 illustrates another IAB network in accordance with variousembodiments.

FIG. 8 schematically illustrates a routing technique for upstreamtraffic in an IAB network, in accordance with various embodiments.

FIG. 9 schematically illustrates a routing technique for downstreamtraffic in an IAB network, in accordance with various embodiments.

FIG. 10 schematically illustrates another routing technique in an IABnetwork in accordance with various embodiments.

FIG. 11 illustrates a procedure for IAB node integration in accordancewith various embodiments.

FIG. 12 illustrates distribution of number of UEs per IAB node, with atotal of 30 UEs, in accordance with various embodiments.

FIG. 13 illustrates distribution of number of UEs per IAB node, with atotal of 90 UEs, in accordance with various embodiments.

FIG. 14 illustrates distribution of number of UEs per IAB node withdelayed parent selection and a total of 30 UEs, in accordance withvarious embodiments.

FIG. 15 illustrates distribution of number of UEs per IAB node withdelayed parent selection and a total of 90 UEs, in accordance withvarious embodiments.

FIGS. 16A-16E illustrate operations of a method for IAB node activation,in accordance with various embodiments.

FIG. 17 is a flowchart for an adaptive code-forwarding scheme inaccordance with various embodiments.

FIG. 18 illustrates an IAB network in accordance with variousembodiments.

FIG. 19 illustrates a packet success rate for different network codingrates, in accordance with various embodiments.

FIG. 20 illustrates a packet success rate for different network inputdata rate and best network coding rate for each scheme, in accordancewith various embodiments.

FIG. 21 illustrates average link transmit (Tx) buffer size, inaccordance with various embodiments.

FIG. 22 is a flowchart of a process in accordance with variousembodiments.

FIG. 23 is a flowchart of another process in accordance with variousembodiments.

FIG. 24 is a flowchart of another process in accordance with variousembodiments.

FIG. 25 illustrates an example architecture of a system of a network, inaccordance with various embodiments.

FIG. 26 illustrates an example architecture of a system including afirst CN, in accordance with various embodiments.

FIG. 27 illustrates an architecture of a system including a second CN inaccordance with various embodiments.

FIG. 28 illustrates an example of infrastructure equipment in accordancewith various embodiments.

FIG. 29 depicts example components of a computer platform or device inaccordance with various embodiments.

FIG. 30 depicts example components of baseband circuitry and radiofrequency end modules in accordance with various embodiments.

FIG. 31 illustrates various protocol functions that may be implementedin a wireless communication device according to various embodiments.

FIG. 32 is a block diagram illustrating components, according to someexample embodiments, able to read instructions from a machine-readableor computer-readable medium (for example, a non-transitorymachine-readable storage medium) and perform any one or more of themethodologies discussed herein.

DETAILED DESCRIPTION

The following detailed description refers to the accompanying drawings.The same reference numbers may be used in different drawings to identifythe same or similar elements. In the following description, for purposesof explanation and not limitation, specific details are set forth suchas particular structures, architectures, interfaces, techniques, etc. inorder to provide a thorough understanding of the various aspects ofvarious embodiments. However, it will be apparent to those skilled inthe art having the benefit of the present disclosure that the variousaspects of the various embodiments may be practiced in other examplesthat depart from these specific details. In certain instances,descriptions of well-known devices, circuits, and methods are omitted soas not to obscure the description of the various embodiments withunnecessary detail. For the purposes of the present document, the phrase“A or B” means (A), (B), or (A and B).

Various embodiments herein provide techniques for integrated access andbackhaul (IAB) nodes. For example, embodiments include techniquesassociated with:

rate-proportional routing for network coding;

utilizing multiple routes in IAB networks;

user equipment (UE) and parent selection for efficient topology in IABnetworks;

establishing efficient IAB topologies; and/or

adaptive coded-forwarding for network coding.

Rate-Proportional Routing for Network Coding

In IAB networks, network coding can be used for enhancing networkreliability and reducing delay. When multiple paths from source todestination exists, the network coded packet segments need to be routedto different paths. How routing is performed on these paths impacts thereliability performance and network load, and thus needs to beinvestigated.

Traditional routing algorithm uses round-robin method to distributepacket segments across different paths, where each path takes turns tobe activated and each time one network coded packet segment is sent tothe activated path. As a result the traffic data is distributed evenlyamong the paths, and each path gets the same amount of data on average.

-   -   Round-robin routing is simple but inefficient in some cases. For        example, if two paths have different supported rates, then        distributing the same amount of data to both of them causes        overloading of the weaker path, or under-loading of the stronger        path. In the first case the weaker path will experience        congestion and longer delay, hence the overall performance is        impacted. In the second case, the stronger path will be        under-utilized and the total data traffic throughput is        impaired.

Embodiments describe a routing solution that distribute network codeddata probabilistically across different paths, where the probability ofsending a packet segment to a path is in proportion to the correspondingsupported data rate.

The described rate-proportional routing algorithm takes into account thedifferences between the supported rates of different paths and thus canincrease network efficiency, enhance reliability and decrease latency.

In a multi-hop mesh network, there might be multiple paths/routesexisting between message source and destination nodes. Using networkcoding on such a network topology can exploit the multi-path diversitybetween source and destination, as shown in FIG. 1 . A packet is brokeninto several segments and network coding (i.e., linear combination) isperformed on these segments to produce more encoded segments. Theseencoded segments are distributed to the multiple paths between sourceand destination. As long as the destination node accumulates enoughencoded segments, the original packet can be recovered and costly higherlayer retransmission and congestion control can be avoided, althoughsome of these paths may experience congestion or link-blockage.

Traditional round-robin routing protocol distributes the network codedpacket segments evenly among the paths. That is, each path receives thesame amount of data. In our proposed solution, we are aware of eachpath's data-transmission capability and distribute packet segmentsaccordingly. Assume there are n paths {r₁, r₂, . . . r_(n)}, and pathr_(i) can support a data rate R_(i). For each packet segment, weindependently generate a random path number x, whose range is {1, 2, . .. , n} and x=i with probability pi=Ri/R, where R is the sum of all therates Ri. The packet segment is then sent to the path rx.

For example, in the IAB network in FIG. 2 , there are two paths betweenthe IAB donor node and UE (Donor-node 1-node 3-UE, and Donor-node 2-node3-UE). Because of congestion at node 1, the supported data rate of link2-3 is only 10% of the other links, hence the left path only supports10% of the data rate for the right one. The network coding is performedat PDCP layer and the PDCP packets arrive at the donor according to aPoisson process. Each packet has a latency bound of 20 ms. That is, ifthe packet is received & decoded at the UE within 20 ms, it isconsidered to have been successfully received; otherwise, it isconsidered a failure.

FIG. 3 compares the packet success rate (the ratio of timely receivedpackets) of round-robin and the rate-proportional routing schemes, withdifferent network coding rate (e.g., the number of encoded segments/thenumber of originally divided segments), under different network inputdata traffic rate. We can see that to achieve the same (or better)reliability (packet success rate), the rate-proportional routing schemerequires much smaller network code rate, which means much less trafficload on the network. Hence more user can be supported with therate-proportional routing scheme.

The following procedure may be used to enable transmission of networkcoded segments in a rate proportional manner:

-   -   1. A node receives a packet to be transmitted to a destination        and segments it into k segments    -   2. Network coded segments are generated from the k segments    -   3. The node identifies the routes {r₁, r₂, . . . , r_(n)} to the        destination. The node also assigns weights {R₁, R₂, . . . ,        R_(n)} corresponding to the routes {r₁, r₂, . . . , r_(n)}.    -   4. The node transmits coded segments on routes r_(i) such that        the number of network coded segments transmitted on r_(i) is        proportional to R_(i).

Ensuring that the weights used above reflect the relative data ratessupported by the corresponding routes is critical for efficientoperation of the above procedure. The following methods can be useddetermine the weights.

Statistics from Destination Node

The destination node can track, for each successfully received packet,the number of network coded segments received on each of the routes {r₁,r₂, . . . , r_(n)}. Given that the destination can decode the packetwhen at least k segments are received, when the total number of receivedsegments, k′, exceeds k for the first time, the number of segmentsreceived on the routes can be represented as fractions {r_(1s)/k′,r2s/k′, . . . } where r1s and r2s are the number of segments received onroute r1 and r2. It is assumed that the source node generates andtransmits some redundant network coded segments (e.g., the number ofsegments transmitted by the source is greater than k). Furthermore, thesegments are initially distributed in equal proportions to the routes{r1, r2, . . . , rn}.

This information can be averaged over many successfully received packetsand reported to the sender. That is, the fraction corresponding to router1 can be an average of the fractions computed for many successfullyreceived packets.

Once the sender receives this information, it can adjust itsdistribution of network coded segments to the different routes based onthe fractions indicated by the destination.

Link Level Signal Quality

The intermediate nodes can transmit to the source node link level signalmeasurement information. For example, for downstream traffic, theintermediate nodes can transmit information about measured RSRP on thelink to the parent node. For upstream traffic the intermediate nodes cantransmit information about measurements of SRS transmissions.

Based on the received link level signal information, the source node candetermine the supported data rates on each link along each of theroutes. Based on this, it can further determine the data rates supportedon each route (although this does not take into account the load at eachof the nodes). The source node can then distribute network codedsegments to different routes in proportion to the data rates determined(e.g., the data rates determined for the routes serve as the weights).

Learning at the Source Node

The source node can use a phased approach, with a first phase in whichit determines the fraction of segments to be distributed to thedifferent routes and a second phase where the segments are distributedaccording to the fractions determined in the first phase. In the firstphase, the source node transmits all network coded segmentscorresponding to a first packet along a first route, all network codedsegments corresponding to a second packet along a second route, and soon. The source can further request an acknowledgement for each of thepackets in the first phase.

The destination node acknowledges the packet upon successful decoding(after reception of adequate network coded segments). Based on theduration to reception of the acknowledgement for packet sent on router_(i), the source can adjust the fraction of segments transmitted viaroute That is, the fraction of segments transmitted via route r_(i) isinversely proportional to the duration to reception of theacknowledgement.

Methods for Utilizing of Multiple Routes in IAB Networks

FIG. 4 illustrates an IAB network in accordance with variousembodiments. Each Integrated Access and Backhaul (IAB) node in an IABnetwork has to support attachment of UEs and other IAB nodes. However,IAB nodes do not have full-fledged base station (gNB) capabilities. AnIAB network leverages the Central Unit-Distributed Unit (CU-DU) splitarchitecture. The Radio resource control (RRC) functionality is placedin the CU of the donor IAB node. Each IAB node functions as a DU. TheIAB node is controlled by the IAB donor in a manner similar to the DUcontrol by the CU. Specifically, the F1 control plane protocol betweenthe CU and the DU is modified to support transmission over multiplehops; the modified F1 protocols enable the IAB donor to control the IABnodes.

Such a network can have multiple “routes” between a donor DU (or CU-UP)and an access IAB node (IAB node directly serving a UE). Routing in IABnetworks is expected to be predominantly centrally controlled; that is,the IAB donor determines the precise route taken by a packet. There isan opportunity to use the multiple routes to obtain throughput gains. Inorder to achieve this goal, it is necessary to be able to route dataalong both/multiple routes to and from the UE.

Embodiments herein provide methods to partition the data such that themultiple routes can be efficiently used and corresponding throughputimprovements realized.

FIG. 5 shows an example of a network architecture for IAB in which thereare multiple routes. There are two routes from the IAB donor gNB to theaccess IAB node of the UE. The access IAB node is connected to twointermediate IAB nodes, each of which is connected to the IAB donor gNB.

Given that IAB nodes do not have PDCP functionality, it is understood(and agreed) that BAP layer is responsible for routing data for a givenUE bearer along multiple routes.

FIG. 6 shows an example protocol architecture for RRC connectivitybetween a UE and an IAB donor.

Each IAB node operates as a combination of a DU (serving the next hop)and an MT (providing connectivity to the parent node). The mobileterminal (MT) of an IAB node embodies UE functionality to enableconnectivity to the parent. The Backhaul Adaptation protocol (BAP) layerperforms the routing functions at the IAB donor and at the IAB nodes.The routing is based on BAP routing identifiers. A BAP routingidentifier is inserted into the header of each packet. The BAP layer atan IAB node is configured with a routing table which enables it todetermine the next hop (e.g., next link to transmit the packet on) basedon the BAP routing ID. The following is a summary of the BAP routing IDand the routing function:

-   -   The BAP routing id (carried in the BAP header) consists of BAP        address and BAP path ID. The path ID is used to distinguish        different routes to the same BAP address.    -   Each BAP address defines a unique destination (unique for IAB        network of one Donor, either an IAB access node, or the IAB        donor)    -   Each BAP routing id has only one entry in the routing table.

Based on the above, there are two ways in which routing information fora given destination node can be encoded in a routing table of an IABnode:

The BAP routing ID can be just the BAP address of the destination node.

There can be multiple BAP routing IDs with the BAP address of thedestination node.

Consider the IAB network shown in FIG. 7 . The access IAB node has IABnode 3 as parent. IAB node 3 is connected to two parents which areconnected to the same IAB donor.

Considering the upstream traffic from the UE, the data split would occurat IAB node 3. Note however, that IAB node 4 has to construct the BAPheader for the UE's data and transmit it on the next hop. One of thesteps in BAP processing at IAB node 4 is to choose a BAP routing ID. Inthis case, given that there are two paths to the same destination (IABdonor gNB), there are two BAP routing IDs. The access IAB node shouldsplit the data such that some portion of the data is assigned the firstBAP routing ID and the remaining is assigned the second BAP routing ID.

However, IAB node 4 does not have means to make a reasonable split ofdata between the two BAP routing IDs.

-   -   The access IAB node is unaware of the topology upstream. It also        does not know the characteristics of the links on the two paths.        Splitting data according to some pre-determined ratio can result        in significant problems. For example, if the supported data rate        on one path is lower than on the other path, and the access IAB        node splits the data equally between the two paths, congestion        can result on one path and under-utilization on the other.

Thus, there does not exist a mechanism currently to systematically splitupstream data into two paths.

Solution 1—Configuring a split at the routing end point (access IAB nodeor donor IAB node)

The example embodiment is described here with respect to upstreamtraffic from the UE to the network.

-   -   1. The CU configures information at the access IAB node 4 for        splitting of the data. This information can include the fraction        of data that should be associated with each of the BAP routing        IDs that can be used to route the UE's traffic (or the traffic        of a specific bearer of the UE).    -   2. The access IAB node assigns BAP routing IDs to each packet        from the UE to be carried over the backhaul in proportion to the        fraction associated with the BAP routing ID.        -   a. The access IAB node may be configured to adjust split on            its own from the ratio configured by the CU, based on flow            control BAP layer feedback received from its parent IAB            nodes. For example, if the IAB donor receives flow control            feedback to indicate that congestion has occurred on the            route corresponding to a BAP routing ID, it can modify the            fractions of data carried over the routes to reduce the data            flow over the congested route.    -   3. The intermediate IAB node which has multiple egress links        forwards the packets via one of the egress links based on the        BAP routing ID.

For example (see FIG. 8 ), BAP routing ID1 can correspond to 4→3→1→donorand BAP routing ID2 can correspond to 4→3→2→donor. The CU may configurenode 4 to associate 70% of the traffic to BAP routing ID1 and 30% of thetraffic to BAP routing ID2. IAB node 4, during its BAP processingoperations, assigns BAP routing ID1 and BAP routing ID2 such that 60%and 40% of the traffic respectively flow over 4→3→1→donor and4→3→2→donor routes.

The CU determines the ratios of traffic to be carried on the differentroutes based on its knowledge of link conditions between nodes along theroutes. When link conditions change, the CU can update the configuredinformation for splitting the data. Or the CU may configure the accessIAB node to adjust split ratio on its own. The configured informationneeds to be separated/organized by the UE and possibly the UE bearer(e.g., different UE's can have different splits, and different UEbearers of the same UE can have different splits).

The same procedure can be applied for downstream traffic (see FIG. 9 ).The IAB donor can be configured with the splitting information asdescribed to ensure that it associates one of multiple BAP routing IDsto downstream packets. However, for downstream, the configurationinformation needs to be distinguished based on the access IAB node, theUE and possibly the UE bearer (e.g., different access IAB nodes canrequire different splits based on the different number of routes;different UEs and different UE bearers of the same UE can have differentsplits).

Solution 2—Configuring Intermediate Node to Split Data Stream

This solution enables an intermediate IAB node to make decisions aboutwhich packets traverse which routes. The example embodiment is describedwith respect to upstream traffic.

-   -   1. The CU configures information for splitting of the data        stream at an intermediate IAB node with multiple parents. This        split information can include the fraction of the ingress data        that should be transmitted on each of the egress links.    -   2. The access IAB node uses a single BAP routing ID for the        traffic to be transmitted via multiple routes (to the donor).        That is, the path-id portion of the BAP routing ID can be        omitted or a default value can be used even if there are        multiple routes.    -   3. The intermediate IAB node, determines that for the BAP        routing ID there are multiple egress links. It splits the        packets between the multiple egress links according to the        configured split.        -   a. The intermediate IAB node may be further configured to            adjust split from the ratio configured by the CU, based on            flow control BAP layer feedbacks received from its parent            IAB nodes (UL case) or children IAB nodes (DL case) on the            routes.

Given that in the above method the split at the intermediate IAB nodesis based on the BAP routing ID, it does not have the ability to treattraffic from different UEs of different UE bearers differently. That is,all traffic to a given destination is split according to the configuredsplit information. In order to enable splitting of different trafficstreams (of UEs, UE bearers), one or more of the following informationcan be included in the BAP header:

UE Id

UE bearer ID

Source address

Then the split configuration can be organized according to thisinformation. For example, one split configuration can be established fora given UE bearer ID at an intermediate IAB node and an different splitconfiguration can be established for a different UE bearer ID at thesame node.

Similar to solution 1, solution 2 can be used for downstream trafficalso. The split configuration would need to account for different accessIAB nodes being destination. Thus, the split configuration at anintermediate IAB node needs to be different for traffic destined todifferent access IAB nodes.

User Equipment Parent Selection for Efficient Topology in IntegratedAccess and Backhaul

Integrated access and backhaul (IAB) nodes can be integrated into thenetwork (referred to as IAB node “activation” below) in differentsequences within the same area. Even if all IAB nodes are to beactivated at about the same time, the completion of the node integrationphases will take different durations for different IAB nodes. There willbe variations in the amount of time taken due to the number of hops andsignal conditions. Given that UEs/MTs can attach to the IAB node uponcompletion of the IAB DU setup, the differences in the durations tocomplete the integration procedure at different IAB nodes can result in:

IAB nodes selecting sub-optimal parents, and

UEs selecting sub-optimal parents.

One consequence of such sub-optimal parent selection is that handoversof the IAB nodes and UEs will need to be performed immediately after thenetwork is setup or even during the network setup. This can impose alarge signalling load in the network and may also be infeasible as thenumber of IAB nodes gets large.

UEs attach to IAB nodes as the IAB nodes are integrated according to thecurrent procedure.

The UE parent selection according to the current/legacy procedures leadsto an uneven distribution of UEs at IAB nodes resulting excessive loadat some nodes and under-utilization at other nodes.

Methods are provided that modify the node integration procedure toenable a more efficient resulting topology.

UE Parent Selection for Efficient Topology in IAB

IAB networks (see, e.g., FIG. 4 ) are setup to improve capacity andcoverage while limiting the cost of backhaul. IAB nodes in an area areexpected to be activated at the same time. This is especially true forscenarios where IAB networks are used to provide additional capacity atevents—e.g., at sporting events and concerts.

IAB nodes can be integrated into the network (referred to as IAB node“activation” below) in different sequences within the same area. Even ifall IAB nodes are to be activated at about the same time, the completionof the node integration phases will take different durations fordifferent IAB nodes. There will be variations in the amount of timetaken due to the number of hops and signal conditions. Given thatUEs/MTs can attach to the IAB node upon completion of the IAB DU setup,the differences in the durations to complete the integration procedureat different IAB nodes can result in:

IAB nodes selecting sub-optimal parents, and

UEs selecting sub-optimal parents.

One consequence of such sub-optimal parent selection is that handoversof the IAB nodes and UEs will need to be performed immediately after thenetwork is setup or even during the network setup. This can impose alarge signalling load in the network and may also be infeasible as thenumber of IAB nodes gets large.

Embodiments provide methods to ensure efficient selection of parents byUEs during the integration procedure so that signalling related tohandovers of UEs and IAB nodes can be avoided or minimized.

Given that the MT of an IAB node functions as a UE, once an IAB node isintegrated into the network, UEs are able to attach to it. For example,if a UE that is attached to a donor IAB node, measures a better RSRP toa newly activated node than to the IAB donor, it switches its parentfrom the IAB donor to the newly activated IAB node (either through acell reselection if the UE is in idle mode or through a networkcontrolled handover if the UE is in connected mode).

IAB nodes follow the same procedures as UEs for attaching to thenetwork. The overall procedure for IAB node integration is shown in FIG.11 below (from 3GPP Technical Standard 38.401 [1]). In the first stagethe IAB MT setup is performed. The MT of an IAB node, in its role as aregular UE, identifies a parent node (another IAB node or an IAB donor).The MT then performs random access and transmits an RRC connection setuprequest to the CU via the parent node. Following that, the backhaul RLCchannel for carrying CP traffic to and from the IAB node is established.This is followed by a routing update phase which includes configurationof BAP routing identifiers and updating of routing tables of the IABdonor DU and all IAB nodes on the path to the IAB node. Following that,in the IAB DU setup phase, the DU functionality of the IAB node isconfigured (which consists of setting up of the F1-C connection betweenthe IAB node and the IAB donor CU). Once this is completed, the IAB nodecan provide service to UEs.

As noted above, different IAB nodes are integrated at different times.If UEs attach to an IAB node immediately after it is integrated, theresult is generally an inefficient and uneven UE association. This isillustrated in FIG. 12 and FIG. 13 . FIG. 12 and FIG. 13 show thedistribution of the number of UEs attached to IAB nodes, with a total of30 and 90 UEs respectively. Table 1 shows the mean and standarddeviation of the number of UEs per IAB node and the number of UEsattached to the IAB donor.

TABLE 1 Details of distribution of number of UEs (UEs allowed to selectparents once IAB node is integrated) Number of UEs Number of UEsattached per IAB node to IAB donor Total number Std. Std. of UEs MeanDeviation Mean Deviation 30 1.88 1.58 13.08 3.66 90 5.65 3.61 39.14 7.82

Clearly the distribution of UEs is very uneven. Some of the unevendistribution of UEs is due to the difference in transmit powers of theIAB donor and the IAB nodes. However, the large proportion of IAB nodeswith no UEs or a very small number of UEs indicates significantinefficiencies.

The above results are compared to a scheme where the UEs do not performparent selection until all the IAB nodes are integrated into thenetwork. FIG. 14 and FIG. 15 show the distribution of number of UEs perIAB node if the UEs perform parent selection only after all IAB nodesare activated. Table 2 shows the mean and standard deviation of thenumber of UEs per IAB node and the number of UEs attached to the IABdonor for the same.

TABLE 2 Details of distribution of number of UEs (UE parent selectiondelayed until all IAB nodes integrated) Number of UEs per Number of UEsattached IAB node to IAB donor Total number Std. Std. of UEs MeanDeviation Mean Deviation 30 2.29 1.50 9.37 2.98 90 6.85 2.93 28.38 5.41

It is clear from the above data that delaying the UE parent selectionuntil all the IAB nodes are integrated can significantly improve thedistribution of UEs and the utilization of IAB nodes. If the UEs areable to select parents as soon as any IAB node is integrated into thenetwork, large numbers of handovers will be needed to achieve anefficient association of UEs to IAB nodes.

Embodiment 1—for UEs in Idle Mode

Based on the above observations, a method is provided below that delaysthe UE parent selection process until all the IAB nodes are integratedinto the network.

-   -   1. It is determined at the CU that IAB nodes need to be        integrated into the network. This can happen based on signalling        between the operator network and the RAN or other signalling.    -   2. A new IAB node performs access (either to the IAB donor or to        one of the already integrated IAB nodes). It is integrated into        the network according to the procedure of FIG. 2 .    -   3. The CU configures the new IAB node to indicate that access by        UEs is barred. Furthermore, access by MTs of IAB nodes is        allowed even though access by UEs is barred. The indication is        transmitted for example through system information.    -   4. UEs may detect and measure the new IAB node; however they do        not select it as a parent.    -   5. Once it is determined that all the IAB nodes are integrated        into the network (which can be based on OAM or other signalling        between the operator network and the RAN), the CU indicates to        the newly integrated IAB nodes that the access barring        restriction of the UEs can be lifted.    -   6. UEs perform and evaluate received signal measurements. UEs in        idle mode select a newly integrated IAB node as a parent if the        selection criteria are met. UEs that are in connected mode        report the measurements to the CU, which performs may perform a        handover to a newly integrated IAB node if the handover criteria        are met.

Example implementation for Step 1 can be as follows. When Donor CUpowers up, it will first setup NGAP with 5GC by sending NG SETUP REQUESTmessage. The NG SETUP RESPONSE message from AMF in 3GPP TechnicalStandard (TS) 38.413 can be enhanced to include an indicator for DonorCU to complete IAB nodes integrations before starting to serve UEs:

9.2.6.2 NG Setup Response

This message is sent by the AMF to transfer application layerinformation for an NG-C interface instance.

Direction: AMF→NG-RAN node

IE type and Semantics Assigned IE/Group Name Presence Range referencedescription Criticality Criticality Message Type M 9.3.1.1 YES rejectAMF Name M 9.3.3.21 YES reject Served GUAMI List 1 YES reject  >ServedGUAMI 1 . . . —  Item <maxnoofServedGUAMIs>  >>GUAMI M 9.3.3.3 — >>Backup AMF O AMF Name —  Name 9.3.3.21 Relative AMF M 9.3.1.32 YESignore Capacity PLMN Support List 1 YES reject  >PLMN Support 1 . . . — Item <maxnoofPLMNs>  >>PLMN Identity M 9.3.3.5 —  >>Slice Support M9.3.1.17 Supported S- —  List NSSAIs per PLMN Criticality Diagnostics O9.3.1.3 YES ignore UE Retention O 9.3.1.117 YES ignore Information DelayUE Serving O ENUMERATED indicates to (True, . . .) RAN, in case of IABDonor CU, not to start serving UEs.

Range bound Explanation maxnoofServedGUAMIs Maximum no. of GUAMIs servedby an AMF. Value is 256. maxnoofPLMNs Maximum no. of PLMNs per message.Value is 12.

Example implementation for Step 3 can be as follows. When an IAB node isbeing integrated and its IAB-DU powers up, it will first setup F1AP withDonor CU by sending F1 SETUP REQUEST message. The F1 SETUP RESPONSEmessage from Donor CU in 3GPP TS 38.473 can be enhanced to include anindicator not to start serving UEs until further notice:

9.2.1.5 F1 Setup Response

This message is sent by the gNB-CU to transfer information associated toan F1-C interface instance.

Direction: gNB-CU→gNB-DU

IE type and Semantics Assigned IE/Group Name Presence Range referencedescription Criticality Criticality Message Type M 9.3.1.1 YES rejectTransaction ID M 9.3.1.23 YES reject gNB-CU Name OPrintableString(SIZE(1 . . . Human YES ignore 150, . . .)) readable nameof the gNB- CU. Cells to be Activated 0 . . . 1 YES reject List  >Cellsto be 1 . . . List of cells to EACH reject  Activated List<maxCellingNBDU> be activated  Item  >> NR CGI M 9.3.1.12 —  >> NR PCI OINTEGER Physical Cell — (0 . . . 1007) ID  >>gNB-CU O 9.3.1.42 RRCcontainer YES reject  System with system  Information information ownedby gNB-CU  >>Available O 9.3.1.65 YES ignore  PLMN List  >>Extended O9.3.1.76 This is YES ignore  Available included if  PLMN List AvailablePLMN List IE is included and if more than 6 Available PLMNs is to besignalled.  >>Delay UE O ENUMERATED indicates to  Serving (True, . . .)DU, in case of IAB-DU, not to start serving UEs in this activated cell.gNB-CU RRC M RRC version YES reject version 9.3.1.70

Range bound Explanation maxCellingNBDU Maximum no. cells that can beserved by a gNB-DU. Value is 512.

Example implementation for Step 5 can be as follows. After all the IABnodes are registered in 5GC and integrated into IAB network, AMF maysend AMF Configuration Update message in NGAP to the Donor CU to startserving UEs:

9.2.6.7 AMF Configuration Update

This message is sent by the AMF to transfer updated information for anNG-C interface instance.

Direction: AMF→NG-RAN node

IE type and Semantics Assigned IE/Group Name Presence Range referencedescription Criticality Criticality Message Type M 9.3.1.1 YES rejectAMF Name O 9.3.3.21 YES reject Served GUAMI List 0 . . . 1 YES reject >Served GUAMI 1 . . .  Item <maxnoofServedGUAMIs>  >>GUAMI M 9.3.3.3 — >>Backup AMF O AMF Name —  Name 9.3.3.21 Relative AMF O 9.3.1.32 YESignore Capacity PLMN Support List 0 . . . 1 YES reject  >PLMN Support 1. . . — Item <maxnoofPLMNs>  >>PLMN Identity M 9.3.3.5 —  >>SliceSupport List M 9.3.1.17 Supported S- — NSSAIs per PLMN AMF TNL 0 . . . 1YES ignore Association to Add List  >AMF TNL 1 . . . —  Association toAdd <maxnoofTNLAssociations>  Item  >>AMF TNL M CP Transport AMFTransport —  Association Address Layer Layer Information informationused 9.3.2.6 to set up the new TNL association.  >>TNL Association O9.3.2.9 —  Usage  >>TNL Address M 9.3.2.10 —  Weight Factor AMF TNL 0 .. . 1 YES ignore Association to Remove List  >AMF TNL 1 . . . — Association to <maxnoofTNLAssociations>  Remove Item  >>AMF TNL M CPTransport AMF Transport —  Association Address Layer Layer Informationinformation used 9.3.2.6 to identify the TNL association to be removed.AMF TNL 0 . . . 1 YES ignore Association to Update List  >AMF TNL 1 . .. —  Association to <maxnoofTNLAssociations>  Update Item  >>AMF TNL MCP Transport AMF Transport —  Association Address Layer LayerInformation information used 9.3.2.6 to identify the TNL association tobe updated.  >>TNL Association O 9.3.2.9 —  Usage  >>TNL Address O9.3.2.10 —  Weight Factor Start Serving UEs O ENUMERATED indicates to(True, . . .) RAN, in case of IAB Donor CU, to start serving UEs.

Range bound Explanation maxnoofServedGUAMIs Maximum no. of GUAMIs servedby an AMF. Value is 256. maxnoofPLMNs Maximum no. of PLMNs per message.Value is 12. maxnoofTNLAssociations Maximum no. of TNL Associationsbetween the NG-RAN node and the AMF. Value is 32.

Then, Donor CU may send GNB-CU CONFIGURATION UPDATE message in F1AP toeach IAB-DU to start serving UEs:

9.2.1.10 gNBb-CU Configuration Update

This message is sent by the gNB-CU to transfer updated informationassociated to an F1-C interface instance.

NOTE: If F1-C signalling transport is shared among several F1-Cinterface instances, this message may transfer updated informationassociated to several F1-C interface instances.

Direction: gNB-CU→gNB-DU

IE type and Semantics Assigned IE/Group Name Presence Range referencedescription Criticality Criticality Message Type M 9.3.1.1 YES rejectTransaction ID M 9.3.1.23 YES reject Cells to be Activated 0 . . . 1List of cells to YES reject List be activated or modified  >Cells to be1 . . . EACH reject  Activated List <maxCellingNBDU>  Item  >> NR CGI M9.3.1.12 —  >> NR PCI O INTEGER Physical Cell ID — (0 . . . 1007)  >>gNB-CU O 9.3.1.42 RRC container YES reject  System with system Information information owned by gNB-CU  >>Available O 9.3.1.65 YESignore  PLMN List  >>Extended O 9.3.1.76 This is included if YES ignore Available PLMN Available PLMN List  List IE is included and if morethan 6 Available PLMNs is to be signalled. Cells to be 0 . . . 1 List ofcells to be YES reject Deactivated List deactivated  >Cells to be 1 . .. EACH reject  Deactivated List <maxCellingNBDU>  Item  >> NR CGI M9.3.1.12 — gNB-CU TNL 0 . . . 1 YES ignore Association To Add List >gNB-CU TNL 1 . . . EACH ignore  Association To<maxnoofTNLAssociations>  Add Item IEs  >>TNL M CP Transport TransportLayer —  Association Layer Address Address of the  Transport Layer9.3.2.4 gNB-CU.  Information  >>TNL M ENUMERATED Indicates whether — Association (ue, non-ue, the TNL association  Usage both, . . .) isonly used for UE-associated signalling, or non- UE-associatedsignalling, or both. For usage of this IE, refer to TS 38.472 [22].gNB-CU TNL 0 . . . 1 YES ignore Association To Remove List  >gNB-CU TNL1 . . . EACH ignore  Association To <maxnoofTNLAssociation>  Remove ItemIEs  >>TNL M CP Transport Transport Layer —  Association Layer AddressAddress of the  Transport Layer 9.3.2.4 gNB-CU.  Address  >>TNL O CPTransport Transport Layer YES reject  Association Layer Address Addressof the  Transport Layer 9.3.2.4 gNB-DU.  Address gNB-  DU gNB-CU TNL 0 .. . 1 YES ignore Association To Update List  >gNB-CU TNL 1 . . . EACHignore  Association To <maxnoofTNLAssociations>  Update Item IEs  >>TNLM CP Transport Transport Layer —  Association Layer Address Address ofthe  Transport Layer 9.3.2.4 gNB-CU.  Address  >>TNL O ENUMERATEDIndicates whether —  Association (ue, non-ue, the TNL association  Usageboth, . . .) is only used for UE-associated signalling, or non-UE-associated signalling, or both. For usage of this IE, refer to TS38.472 [22]. Cells to be barred 0 . . .1 List of cells to be YES ignoreList barred.  >Cells to be barred 1 . . . EACH ignore  List Item<maxCellingNBDU>  >>NR CGI M 9.3.1.12 —  >> Cell Barred M ENUMERATED —(barred, not- barred, . . .) Protected E-UTRA 0 . . . 1 List ofProtected YES reject Resources List E-UTRA Resources.  >Protected E- 1 .. . EACH reject  UTRA Resources <maxCellineNB>  List Item  >>Spectrum MINTEGER Indicates the E- —  Sharing Group (1 . . . UTRA cells  IDmaxCellineNB) involved in resource coordination with the NR cellsaffiliated with the same Spectrum Sharing Group ID.  >> E-UTRA 1 List ofapplicable —  Cells List E-UTRA cells.  >>> E-UTRA 1 . . . —  Cells ListItem <maxCellineNB>  >>>>EUTRA M BIT Indicates the E- —  Cell IDSTRING(SIZE(28)) UTRAN Cell Global Identifier as defined in subclause9.2.14 in TS 36.423 [9].  >>>>Served E- M 9.3.1.64 —  UTRA Cell Information Start Serving UEs for O ENUMERATED indicates to DU, in YESignore All Activated Cells (True, . . .) case of IAB-DU, to startserving UEs for all activated cells.

Embodiment 2—for UEs in Connected Mode

The network can selectively allow handovers of UEs to newly integratedIAB nodes, based on knowledge of other IAB nodes that are to beintegrated.

-   -   1. It is determined at the CU that IAB nodes need to be        integrated into the network. This can happen based on OAM        signalling or other signalling between the operator network and        the RAN.    -   2. A new IAB node performs access (either to the IAB donor or to        one of the already integrated IAB nodes). It is integrated into        the network according to the procedure of FIG. 2 .    -   3. A UE performs measurement of the newly integrated IAB node        and reports the measurement to the CU (for example, the        measurement report may be triggered based on a handover        measurement event such as A3). The CU checks if there are other        IAB nodes pending integration near the newly integrated IAB        node. If the CU identifies one or more such IAB nodes, it delays        the handover of the UE until the other IAB nodes pending        integration are integrated into the network.

Delaying of handover can have unfavourable consequences for the UEs andthe system (UEs experience increased interference, and degradedperformance). For this reason, instead of performing handovers of UEs,the network can transition the UE to Idle mode (using e.g., an RRCconnection release message) and in addition indicate a minimum durationfor which the UE should remain in idle mode. The duration covers theperiod of time needed for integration of the IAB nodes. The UEs canperform parent selection and reattach to the network, and may find anewly integrated IAB node to be a more suitable parent than the previousparent.

Methods for Establishing Efficient Integrated Access and BackhaulNetwork Topologies

As discussed above, IAB nodes can be integrated into the network(referred to as IAB node “activation”) in different sequences within thesame area. Even if all IAB nodes are to be activated at about the sametime, the completion of the node integration phases will take differentdurations for different IAB nodes. There will be variations in theamount of time taken due to the number of hops and signal conditions.Given that UEs/MTs can attach to the IAB node upon completion of the IABDU setup, the differences in the durations to complete the integrationprocedure at different IAB nodes can result in:

IAB nodes selecting sub-optimal parents, and

UEs selecting sub-optimal parents.

One consequence of such sub-optimal parent selection is that handoversof the IAB nodes and UEs will need to be performed immediately after thenetwork is setup or even during the network setup. This can impose alarge signaling load in the network and may also be infeasible as thenumber of IAB nodes gets large.

This disclosure provides methods to ensure efficient selection ofparents by IAB nodes and UEs during the integration procedure so thatsignaling related to handovers of UEs and IAB nodes can be avoided orminimized.

Various embodiments enable more efficient network operations andimproved network capacity.

IAB networks (see, e.g., FIG. 4 ) are setup to improve capacity andcoverage while limiting the cost of backhaul. IAB nodes in an area areexpected to be activated at the same time. This is especially true forscenarios where IAB networks are used to provide additional capacity atevents—e.g., at sporting events and concerts.

IAB nodes can be integrated into the network (referred to as IAB node“activation” below) in different sequences within the same area. Even ifall IAB nodes are to be activated at about the same time, the completionof the node integration phases will take different durations fordifferent IAB nodes. There will be variations in the amount of timetaken due to the number of hops and signal conditions. Given thatUEs/MTs can attach to the IAB node upon completion of the IAB DU setup,the differences in the durations to complete the integration procedureat different IAB nodes can result in:

IAB nodes selecting sub-optimal parents, and

UEs selecting sub-optimal parents.

One consequence of such sub-optimal parent selection is that handoversof the IAB nodes and UEs will need to be performed immediately after thenetwork is setup or even during the network setup. This can impose alarge signalling load in the network and may also be infeasible as thenumber of IAB nodes gets large.

This disclosure provides methods to ensure efficient selection ofparents by IAB nodes and UEs during the integration procedure so thatsignalling related to handovers of UEs and IAB nodes can be avoided orminimized. While the general principles here are explained for IAB nodeparent selection, similar techniques can be applied to UEs as well.

Methods for Efficient IAB Node Parent Selection

IAB nodes follow the same procedures as UEs for attaching to thenetwork. The overall procedure for IAB node integration is shown in FIG.11 (from 3GPP TS 38.401). In the first stage the IAB MT setup isperformed. The MT of an IAB node, in its role as a regular UE,identifies a parent node (another IAB node or an IAB donor). The MT thenperforms random access and transmits an RRC connection setup request tothe CU via the parent node. Following that, the backhaul RLC channel forcarrying CP traffic to and from the IAB node is established. This isfollowed by a routing update phase which includes configuration of BAProuting identifiers and updating of routing tables of the IAB donor DUand all IAB nodes on the path to the IAB node. Following that, in theIAB DU setup phase, the DU functionality of the IAB node is configured(which includes setting up of the F1-C connection between the IAB nodeand the IAB donor CU). Once this is completed, the IAB node can provideservice to UEs.

The sequence in which the IAB nodes are activated and integrated intothe network greatly influences the resulting topology. A comparison oftopologies resulting from the following may be analyzed:

-   -   randomly chosen sequence of IAB nodes is activated and        integrated into the network    -   The sequence in which IAB nodes are integrated into the network        is based on the maximum RSRPs across all possible links between        nodes that are already integrated into the network and nodes        that are not yet integrated. For purposes of discussion this is        referred to as the Ideal sequence.

The desired sequence is described as an algorithm below:

-   -   The set of potential parents P initially consists of the IAB        donor only.    -   While there are IAB nodes to be activated:        -   From the set of un-activated IAB nodes, select the IAB node            N with the strongest signal to a potential parent P_(i) in            P, make P_(i) the parent node of N, and activate N        -   Add N to P

The analysis shows that the ideal sequence results in a much moreefficient topology of the IAB network.

The ideal sequence of activations relies on knowledge of signalmeasurements such as RSRP measured at the IAB nodes. Note however, thatthe ideal sequence of node activations cannot be implemented in apractical network due to the fact that the centralized unit (CU)—whichcontrols topology of the network—does not have information about suchmeasurements.

Embodiments provide methods that approach the performance of the idealsequence while not having the requirement of centralized measurementinformation.

Node Activation Based on Threshold Changing Over Time

The method consists of transmitting a message indicating the signallevel threshold (such as RSRP threshold) by nodes that are integratedinto the network. The threshold is used by IAB nodes to determinewhether to select the node the node indicating the threshold as aparent.

This is illustrated using the FIGS. 16A-D and 17, as discussed below.

-   -   1. Step 1: The set of integrated nodes initially consists of        only the IAB donor. The IAB donor indicates a signal level        threshold (−65 dBm for example). IAB nodes perform measurements        for parent selection. For example, IAB node 1 performs        measurements and finds that the RSRP of the IAB donor's signal        is at least −65 dBm. IAB node 1 selects the IAB donor as parent,        performs access and follows the procedure of FIG. 1 to be        integrated into the network.    -   2. Step 2: The set of integrated nodes consists of the IAB donor        and IAB node 1.        -   a. The IAB donor reduces the indicated threshold to −70 dBm.            IAB node 1 concurrently indicates an RSRP threshold of −70            dBm.        -   b. IAB node 6 and 8 perform measurements and find that the            RSRP of the IAB donor's signal is above −70 dBm. Node 6 and            8 also find that the RSRP of IAB node 1's signal is below            −70 dBm. Based on this nodes 6 and 8 select the IAB donor as            parent and is integrated into the network.        -   c. IAB node 2 performs measurements and finds that the RSRP            of IAB node 1's signal is above the −70 dBm threshold. IAB            node also finds the IAB donor's RSRP to be below the −70 dBm            threshold. Based on this IAB node 2 selects IAB node 1 as            parent and is integrated into the network.    -   3. Step 3: The set of integrated nodes consists of the IAB        donor, IAB nodes 1, 2, 6 and 8.        -   a. The IAB donor and IAB node 1 reduce the indicated            threshold to −75 dBm. IAB nodes 2, 6 and 8 concurrently            indicate an RSRP threshold of −75 dBm.        -   b. IAB node 4 performs measurements and finds IAB node 6's            signal to be above the threshold (and signals of the other            integrated nodes to be below the threshold). It selects node            6 as a parent and is integrated into the network.        -   c. IAB node 9 performs measurements and finds IAB node 8's            signal to be above the threshold (and signals of the other            integrated nodes to be below the threshold). It selects node            8 as a parent and is integrated into the network.    -   4. Step 4: The set of integrated nodes consists of the IAB        donor, IAB nodes 1, 2, 4, 6, 8 and 9.        -   a. The IAB donor and IAB node 1, 2, 6, 8 reduce the            indicated threshold to −80 dBm. IAB node 4 and IAB node 9            concurrently indicate an RSRP threshold of −80 dBm.        -   b. IAB node 5 performs measurements and finds IAB node 4's            signal to be above the threshold (and signals of the other            integrated nodes to be below the threshold). It selects node            4 as a parent and is integrated into the network.        -   c. IAB node 3 performs measurements and finds IAB node 2's            signal to be above the threshold (and signals of the other            integrated nodes to be below the threshold). It selects node            2 as a parent and is integrated into the network.    -   5. Step 5: The set of integrated nodes consists of the IAB        donor, IAB nodes 1, 2, 3, 4, 5, 6, 8 and 9.        -   a. The IAB donor and IAB node 1, 2, 4, 6, 8 and 9 reduce the            indicated threshold to −90 dBm. IAB node 3 and IAB node 5            concurrently indicate an RSRP threshold of −90 dBm. Note            that the threshold increment steps need not be the same            size. However, all integrated nodes indicate the same            threshold value.        -   b. IAB node 7 performs measurements and finds both the IAB            donor and IAB node 9's RSRP to be above the threshold (and            signals of the other integrated nodes to be below the            threshold). It also finds the IAB donor's RSRP to be higher            than that of IAB node 9. It selects the IAB donor as a            parent and is integrated into the network.

The thresholds and increments of the thresholds shown are examples.

The indication of the threshold at any given time is preferably providedthrough broadcast system information of the cell. For example, the IABdonor can broadcast the threshold value in a system information blockmessage. Similarly, the IAB nodes that are integrated into the networkcan broadcast the threshold value in a system information block message.The threshold values broadcast by the IAB donor and the integrated IABnodes should be substantially similar, although adjustments to favoursome nodes over others can be performed (and would result in slightlydifferent values of thresholds broadcast by the nodes).

Additionally, the update of the threshold is performed by the IAB donorand the integrated IAB nodes in a synchronous manner. The systeminformation broadcast of each node is controlled by the CU. Using step 2above as an example, after node 1 is integrated into the network, the CUupdates the system information message (to reflect the updatedthreshold) transmitted by the IAB donor and also starts transmission ofthe system information from IAB node 1 with the updated threshold. Inanother embodiment, the CU may generate the system information messagewith the updated threshold and send it to the IAB node 1, or may sendthe updated threshold over F1AP so that the IAB node 1 can generate thecorresponding system information message. Similarly at step 3, the CUupdates the system information messages transmitted by the IAB donor andIAB node 1, and initiates transmission of the system information messagefrom IAB nodes 2, 6 and 8 (with the updated threshold). The updates ofthe threshold can be performed periodically with enough duration betweenthe updates to enable new IAB nodes to select parents and integrate intothe network.

Node Activation Based on Location Information

Location information of IAB nodes can be used to sequence the activationof nodes to yield a topology close to the ideal sequence. In situationswhere the radio links between the IAB donor and the IAB nodes and amongthe IAB nodes are line of sight, the location based activation mayprovide good performance.

-   -   1. The CU receives location information of all IAB nodes in the        area. This could be through the operators OAM (Operations and        Management) communication. The IAB nodes can provide their        location to the OAM server using means not described here.    -   2. Based on the location information, the CU computes        approximate expected RSRP values for each pair of nodes.    -   3. The algorithm shown for ideal sequencing is then followed to        integrate the IAB nodes. Collection of measurements of        non-integrated IAB nodes

In order to facilitate the ideal sequencing, it may be possible tocollect measurements of IAB nodes using a non-3gpp communication path.For example, IAB nodes and IAB donors may be equipped with WiFi orBluetooth capabilities.

-   -   1. IAB nodes that are able to detect and measure the IAB donor,        indicate their measurements to the IAB donor via the alternate        communication path.    -   2. The IAB donor selects the IAB node (node A) that has the best        measurement and indicates that it can integrate into the        network. Node A performs access to the IAB node and is        integrated.    -   3. The integrated node set I now consists of the IAB donor and        node A. The IAB nodes now perform measurements of the IAB donor        and node A and report this via the alternate path. The IAB donor        selects the pair (I, c) where I is in I and c is an unintegrated        IAB node, such that the RSRP of I measured at c is the highest        of all such pairs. The IAB donor then indicates that c should        integrate into the network.    -   4. This process continues until all IAB nodes are integrated.

Adaptive Coded-Forwarding for Network Coding

In IAB networks, network coding can be used for enhancing networkreliability and reducing delay. When network coded packet segments aresent through the network with possibly complex topology and withdifferent capacity and reliability conditions on different links, howdata are forwarded through the links can impact the end-to-endreliability performance and the traffic load on the network, and thusneeds to be investigated.

In an IAB network, between a source and a destination there may existmultiple paths, each of which may be composed of multiple hops. On eachpath data packets/packet segments are usually forwarded along the linkswithout additional processing, which can be called the direct-forwardingstrategy.

The direct-forwarding strategy fails to utilize the properties ofnetwork coding and is blind to the complex network conditions in IABnetworks, and so becomes inefficient in some cases. The following aretwo examples. 1) If a multi-hop path has a weak link with a higherpacket dropping rate, then network coding with direct-forwarding needsto provide enough redundant coded segments over the whole path toguarantee end-to-end reliability, which leads to unnecessary networkload for the good links on the path. 2) If two paths are merging andeach of them carries some encoded segments of the same packet, then itcould be the case that the combined redundancy for the merged section ismore than necessary for the required reliability on the correspondinglinks, which again unnecessarily overloads that part of network.

Embodiments herein provide an adaptive coded-forwarding scheme fornetwork coding on IAB networks, which 1) supplements thedirect-forwarding scheme by encoding and forwarding extra outgoingsymbols if possible when the reliability target on a link is not met,and 2) throttles the number of outgoing symbols in case of excessredundancy (when the reliability target on a link is already met).

The adaptive coded-forwarding scheme supplements direct forwarding andcan forward network coded data in a smart way that takes into accountthe complex network topology, different capacity and reliabilityconditions on different links, and the properties of network coding. Itimproves the end-to-end reliability performance and the traffic load onthe IAB network.

In a multi-hop IAB network, there might be multiple paths/routesexisting between message source and destination nodes. Network coding onsuch a network topology can exploit the multi-path diversity betweensource and destination to enhance reliability. In network coding, apacket is broken into several segments and linear combinations of thesesegments are formed to produce more encoded segments, which are thendistributed to the multiple paths between source and destination. Aslong as the destination node accumulates enough encoded segments (notnecessarily all of them), the original packet can be recovered andcostly higher layer retransmission and congestion control can beavoided, although some of the paths may experience congestion orlink-blockage.

The encoded packet segments are usually forwarded along the links ofeach path without additional processing, which is called thedirect-forwarding scheme. In embodiments of an adaptive coded-forwardingscheme, basic forwarding may be performed for the encoded segments, butwith the one or both of the following two strategies added:

-   -   (1) When there is enough number of coded segments for a packet        received, a node decodes the packet and checks how many encoded        segments each outgoing link has sent. If it is less than a        predefined number that matches the needed link reliability, then        the node encodes the packet into more segments and supplies the        link with these extra coded segments until the predefined number        is reached. During the period when the node is waiting for        enough number of coded segments to decode the packet, it        continues to forward the coded segments that it has received.        This ensures that the adaptive coded forwarding scheme does not        increase latency.    -   (2) Regardless of (1), each node keeps track of how many encoded        segments of each packet has been transmitted on every outgoing        link. If there are already enough segments for the required        reliability (reaching the predefined number mentioned above), we        stop the transmission of any additional segments from the same        packet on the corresponding link.

The flowchart for the adaptive coded-forwarding scheme is shown in FIG.17 for each packet for each time slot, assuming the predefined number ofencoded segments is M_(ij) for link j of node i. Note that for each linkthere are two buffers for transmission, a pre-Tx buffer and a Tx buffer.

For reference, FIG. 6 shows a protocol architecture for IAB. Networkcoding in IAB is preferably performed at the Backhaul Adaptationprotocol (BAP) layer. This allows network coding to operate between theIAB donor DU and the access IAB node of the UE (IAB node 2).Furthermore, adaptive coded forwarding can be performed at intermediateIAB nodes such as IAB node 1.

The performances of the two forwarding schemes is compared usingsimulations on the IAB network (connected with two UEs through two IABnodes) in FIG. 18 . The comparison is limited to the backhaul links(e.g., links between the donor DU and the access IAB node) as the UE isnot involved in the network coding operation. In this network, there aretwo paths between the IAB donor node and UE1 (Donor-node 1-node 3-UE1access node, and Donor-node 2 node 3-UE1 access node), whereas for UE2there is only one path (Donor-node 2-UE2 access node). Because ofcongestion at node 1, the supported data rate of link 1-3 is only 2% ofthe other links. Furthermore, because the link between node 3 and UE1access node is weak due to blockage or mobility, the packet droppingrate is high (20%). The network coding is performed at BAP layer and theupper layer packets arrive at the donor DU according to a Poissonprocess. Each packet has a latency bound of 20 ms. That is, if thepacket is received & decoded at the destination within 20 ms, it isconsidered to have been successfully received; otherwise, it isconsidered a failure. The average packet arrival rate are the same forboth UEs, and the routing scheme is rate-proportional, where at thedonor each UE's packet segments are distributed to each available pathwith a probability in proportion to the corresponding supported datarate. In the simulations we fix the network coding rate of UE2 (10%redundancy) but change it for UE1, differently for each forwardingscheme. For direct-forwarding, no re-encoding is performed in the middleof any path, so we change the overall network coding rate for UE1. Foradaptive coded-forward, we only change the network coding rate for thelink node 3-UE1 access node (e.g., the weak link) but keep the networkcoding rate fixed (10% redundancy, same as for UE2) for the other links.For each UE the network coding rate on each link determines the“pre-defined number” M_(ij) in the adaptive coded-forwarding scheme.

In FIG. 19 , the packet success rates (the ratio of timely receivedpackets) of direct-forwarding (NC-DF in the plot) and our adaptivecoded-forwarding (NC-ACF in the plot) schemes are shown, with differentnetwork coding rate to provide redundancy for the weak link node 3-UE1access node, under different network input data traffic rate. Todemonstrate the proportion of coding redundancy, the reciprocal ofnetwork coding rate is used in the plot. As shown, when the input datarate is fixed, with different network coding rates the packet successrates are different for each scheme. However, the best success rateachieved under the adaptive coded-forwarding scheme is considerablyhigher than the direct-forwarding scheme. This is more clearlyillustrated in FIG. 20 , where for different network coding rates thehighest packet success rate of each scheme is plotted under differentinput data rates. Given a reliability target of 95% or above, theadaptive coded-forwarding scheme improves 15%-20% on the supported inputdata rate over direct forwarding. Moreover, the Tx buffer sizes(averaged over time and links) for the two schemes are shown in FIG. 21, which reflect the traffic load of the network. As network codingredundancy is increased, the adaptive coded-forwarding scheme inducesless network traffic.

Systems and Implementations

FIG. 25 illustrates an example architecture of a system 2500 of anetwork, in accordance with various embodiments. The followingdescription is provided for an example system 2500 that operates inconjunction with the LTE system standards and 5G or NR system standardsas provided by 3GPP technical specifications. However, the exampleembodiments are not limited in this regard and the described embodimentsmay apply to other networks that benefit from the principles describedherein, such as future 3GPP systems (e.g., Sixth Generation (6G))systems, IEEE 802.16 protocols (e.g., WMAN, WiMAX, etc.), or the like.

As shown by FIG. 25 , the system 2500 includes UE 2501 a and UE 2501 b(collectively referred to as “UEs 2501” or “UE 2501”). In this example,UEs 2501 are illustrated as smartphones (e.g., handheld touchscreenmobile computing devices connectable to one or more cellular networks),but may also comprise any mobile or non-mobile computing device, such asconsumer electronics devices, cellular phones, smartphones, featurephones, tablet computers, wearable computer devices, personal digitalassistants (PDAs), pagers, wireless handsets, desktop computers, laptopcomputers, in-vehicle infotainment (IVI), in-car entertainment (ICE)devices, an Instrument Cluster (IC), head-up display (HUD) devices,onboard diagnostic (OBD) devices, dashtop mobile equipment (DME), mobiledata terminals (MDTs), Electronic Engine Management System (EEMS),electronic/engine control units (ECUs), electronic/engine controlmodules (ECMs), embedded systems, microcontrollers, control modules,engine management systems (EMS), networked or “smart” appliances, MTCdevices, M2M, IoT devices, and/or the like.

In some embodiments, any of the UEs 2501 may be IoT UEs, which maycomprise a network access layer designed for low-power IoT applicationsutilizing short-lived UE connections. An IoT UE can utilize technologiessuch as M2M or MTC for exchanging data with an MTC server or device viaa PLMN, ProSe or D2D communication, sensor networks, or IoT networks.The M2M or MTC exchange of data may be a machine-initiated exchange ofdata. An IoT network describes interconnecting IoT UEs, which mayinclude uniquely identifiable embedded computing devices (within theInternet infrastructure), with short-lived connections. The IoT UEs mayexecute background applications (e.g., keep-alive messages, statusupdates, etc.) to facilitate the connections of the IoT network.

The UEs 2501 may be configured to connect, for example, communicativelycouple, with an or RAN 2510. In embodiments, the RAN 2510 may be an NGRAN or a 5G RAN, an E-UTRAN, or a legacy RAN, such as a UTRAN or GERAN.As used herein, the term “NG RAN” or the like may refer to a RAN 2510that operates in an NR or 5G system 2500, and the term “E-UTRAN” or thelike may refer to a RAN 2510 that operates in an LTE or 4G system 2500.The UEs 2501 utilize connections (or channels) 2503 and 2504,respectively, each of which comprises a physical communicationsinterface or layer (discussed in further detail below).

In this example, the connections 2503 and 2504 are illustrated as an airinterface to enable communicative coupling, and can be consistent withcellular communications protocols, such as a GSM protocol, a CDMAnetwork protocol, a PTT protocol, a POC protocol, a UMTS protocol, a3GPP LTE protocol, a 5G protocol, a NR protocol, and/or any of the othercommunications protocols discussed herein. In embodiments, the UEs 2501may directly exchange communication data via a ProSe interface 2505. TheProSe interface 2505 may alternatively be referred to as a SL interface2505 and may comprise one or more logical channels, including but notlimited to a PSCCH, a PSSCH, a PSDCH, and a PSBCH.

The UE 2501 b is shown to be configured to access an AP 2506 (alsoreferred to as “WLAN node 2506,” “WLAN 2506,” “WLAN Termination 2506,”“WT 2506” or the like) via connection 2507. The connection 2507 cancomprise a local wireless connection, such as a connection consistentwith any IEEE 802.11 protocol, wherein the AP 2506 would comprise awireless fidelity (Wi-Fi®) router. In this example, the AP 2506 is shownto be connected to the Internet without connecting to the core networkof the wireless system (described in further detail below). In variousembodiments, the UE 2501 b, RAN 2510, and AP 2506 may be configured toutilize LWA operation and/or LWIP operation. The LWA operation mayinvolve the UE 2501 b in RRC_CONNECTED being configured by a RAN node2511 a-b to utilize radio resources of LTE and WLAN. LWIP operation mayinvolve the UE 2501 b using WLAN radio resources (e.g., connection 2507)via IPsec protocol tunneling to authenticate and encrypt packets (e.g.,IP packets) sent over the connection 2507. IPsec tunneling may includeencapsulating the entirety of original IP packets and adding a newpacket header, thereby protecting the original header of the IP packets.

The RAN 2510 can include one or more AN nodes or RAN nodes 2511 a and2511 b (collectively referred to as “RAN nodes 2511” or “RAN node 2511”)that enable the connections 2503 and 2504. As used herein, the terms“access node,” “access point,” or the like may describe equipment thatprovides the radio baseband functions for data and/or voice connectivitybetween a network and one or more users. These access nodes can bereferred to as BS, gNBs, RAN nodes, eNBs, NodeBs, RSUs, TRxPs or TRPs,and so forth, and can comprise ground stations (e.g., terrestrial accesspoints) or satellite stations providing coverage within a geographicarea (e.g., a cell). As used herein, the term “NG RAN node” or the likemay refer to a RAN node 2511 that operates in an NR or 5G system 2500(for example, a gNB), and the term “E-UTRAN node” or the like may referto a RAN node 2511 that operates in an LTE or 4G system 2500 (e.g., aneNB). According to various embodiments, the RAN nodes 2511 may beimplemented as one or more of a dedicated physical device such as amacrocell base station, and/or a low power (LP) base station forproviding femtocells, picocells or other like cells having smallercoverage areas, smaller user capacity, or higher bandwidth compared tomacrocells.

In some embodiments, all or parts of the RAN nodes 2511 may beimplemented as one or more software entities running on server computersas part of a virtual network, which may be referred to as a CRAN and/ora virtual baseband unit pool (vBBUP). In these embodiments, the CRAN orvBBUP may implement a RAN function split, such as a PDCP split whereinRRC and PDCP layers are operated by the CRAN/vBBUP and other L2 protocolentities are operated by individual RAN nodes 2511; a MAC/PHY splitwherein RRC, PDCP, RLC, and MAC layers are operated by the CRAN/vBBUPand the PHY layer is operated by individual RAN nodes 2511; or a “lowerPHY” split wherein RRC, PDCP, RLC, MAC layers and upper portions of thePHY layer are operated by the CRAN/vBBUP and lower portions of the PHYlayer are operated by individual RAN nodes 2511. This virtualizedframework allows the freed-up processor cores of the RAN nodes 2511 toperform other virtualized applications. In some implementations, anindividual RAN node 2511 may represent individual gNB-DUs that areconnected to a gNB-CU via individual F1 interfaces (not shown by FIG. 25). In these implementations, the gNB-DUs may include one or more remoteradio heads or RFEMs (see, e.g., FIG. 28 ), and the gNB-CU may beoperated by a server that is located in the RAN 2510 (not shown) or by aserver pool in a similar manner as the CRAN/vBBUP. Additionally oralternatively, one or more of the RAN nodes 2511 may be next generationeNBs (ng-eNBs), which are RAN nodes that provide E-UTRA user plane andcontrol plane protocol terminations toward the UEs 2501, and areconnected to a 5GC (e.g., CN 2720 of FIG. 27 ) via an NG interface(discussed infra).

In V2X scenarios one or more of the RAN nodes 2511 may be or act asRSUs. The term “Road Side Unit” or “RSU” may refer to any transportationinfrastructure entity used for V2X communications. An RSU may beimplemented in or by a suitable RAN node or a stationary (or relativelystationary) UE, where an RSU implemented in or by a UE may be referredto as a “UE-type RSU,” an RSU implemented in or by an eNB may bereferred to as an “eNB-type RSU,” an RSU implemented in or by a gNB maybe referred to as a “gNB-type RSU,” and the like. In one example, an RSUis a computing device coupled with radio frequency circuitry located ona roadside that provides connectivity support to passing vehicle UEs2501 (vUEs 2501). The RSU may also include internal data storagecircuitry to store intersection map geometry, traffic statistics, media,as well as applications/software to sense and control ongoing vehicularand pedestrian traffic. The RSU may operate on the 5.9 GHz Direct ShortRange Communications (DSRC) band to provide very low latencycommunications required for high speed events, such as crash avoidance,traffic warnings, and the like. Additionally or alternatively, the RSUmay operate on the cellular V2X band to provide the aforementioned lowlatency communications, as well as other cellular communicationsservices. Additionally or alternatively, the RSU may operate as a Wi-Fihotspot (2.4 GHz band) and/or provide connectivity to one or morecellular networks to provide uplink and downlink communications. Thecomputing device(s) and some or all of the radiofrequency circuitry ofthe RSU may be packaged in a weatherproof enclosure suitable for outdoorinstallation, and may include a network interface controller to providea wired connection (e.g., Ethernet) to a traffic signal controllerand/or a backhaul network.

Any of the RAN nodes 2511 can terminate the air interface protocol andcan be the first point of contact for the UEs 2501. In some embodiments,any of the RAN nodes 2511 can fulfill various logical functions for theRAN 2510 including, but not limited to, radio network controller (RNC)functions such as radio bearer management, uplink and downlink dynamicradio resource management and data packet scheduling, and mobilitymanagement.

In embodiments, the UEs 2501 can be configured to communicate using OFDMcommunication signals with each other or with any of the RAN nodes 2511over a multicarrier communication channel in accordance with variouscommunication techniques, such as, but not limited to, an OFDMAcommunication technique (e.g., for downlink communications) or a SC-FDMAcommunication technique (e.g., for uplink and ProSe or sidelinkcommunications), although the scope of the embodiments is not limited inthis respect. The OFDM signals can comprise a plurality of orthogonalsubcarriers.

In some embodiments, a downlink resource grid can be used for downlinktransmissions from any of the RAN nodes 2511 to the UEs 2501, whileuplink transmissions can utilize similar techniques. The grid can be atime-frequency grid, called a resource grid or time-frequency resourcegrid, which is the physical resource in the downlink in each slot. Sucha time-frequency plane representation is a common practice for OFDMsystems, which makes it intuitive for radio resource allocation. Eachcolumn and each row of the resource grid corresponds to one OFDM symboland one OFDM subcarrier, respectively. The duration of the resource gridin the time domain corresponds to one slot in a radio frame. Thesmallest time-frequency unit in a resource grid is denoted as a resourceelement. Each resource grid comprises a number of resource blocks, whichdescribe the mapping of certain physical channels to resource elements.Each resource block comprises a collection of resource elements; in thefrequency domain, this may represent the smallest quantity of resourcesthat currently can be allocated. There are several different physicaldownlink channels that are conveyed using such resource blocks.

According to various embodiments, the UEs 2501 and the RAN nodes 2511communicate data (for example, transmit and receive) data over alicensed medium (also referred to as the “licensed spectrum” and/or the“licensed band”) and an unlicensed shared medium (also referred to asthe “unlicensed spectrum” and/or the “unlicensed band”). The licensedspectrum may include channels that operate in the frequency range ofapproximately 400 MHz to approximately 3.8 GHz, whereas the unlicensedspectrum may include the 5 GHz band.

To operate in the unlicensed spectrum, the UEs 2501 and the RAN nodes2511 may operate using LAA, eLAA, and/or feLAA mechanisms. In theseimplementations, the UEs 2501 and the RAN nodes 2511 may perform one ormore known medium-sensing operations and/or carrier-sensing operationsin order to determine whether one or more channels in the unlicensedspectrum is unavailable or otherwise occupied prior to transmitting inthe unlicensed spectrum. The medium/carrier sensing operations may beperformed according to a listen-before-talk (LBT) protocol.

LBT is a mechanism whereby equipment (for example, UEs 2501 RAN nodes2511, etc.) senses a medium (for example, a channel or carrierfrequency) and transmits when the medium is sensed to be idle (or when aspecific channel in the medium is sensed to be unoccupied). The mediumsensing operation may include CCA, which utilizes at least ED todetermine the presence or absence of other signals on a channel in orderto determine if a channel is occupied or clear. This LBT mechanismallows cellular/LAA networks to coexist with incumbent systems in theunlicensed spectrum and with other LAA networks. ED may include sensingRF energy across an intended transmission band for a period of time andcomparing the sensed RF energy to a predefined or configured threshold.

Typically, the incumbent systems in the 5 GHz band are WLANs based onIEEE 802.11 technologies. WLAN employs a contention-based channel accessmechanism, called CSMA/CA. Here, when a WLAN node (e.g., a mobilestation (MS) such as UE 2501, AP 2506, or the like) intends to transmit,the WLAN node may first perform CCA before transmission. Additionally, abackoff mechanism is used to avoid collisions in situations where morethan one WLAN node senses the channel as idle and transmits at the sametime. The backoff mechanism may be a counter that is drawn randomlywithin the CWS, which is increased exponentially upon the occurrence ofcollision and reset to a minimum value when the transmission succeeds.The LBT mechanism designed for LAA is somewhat similar to the CSMA/CA ofWLAN. In some implementations, the LBT procedure for DL or ULtransmission bursts including PDSCH or PUSCH transmissions,respectively, may have an LAA contention window that is variable inlength between X and Y ECCA slots, where X and Y are minimum and maximumvalues for the CWSs for LAA. In one example, the minimum CWS for an LAAtransmission may be 9 microseconds (μs); however, the size of the CWSand a MCOT (for example, a transmission burst) may be based ongovernmental regulatory requirements.

The LAA mechanisms are built upon CA technologies of LTE-Advancedsystems. In CA, each aggregated carrier is referred to as a CC. A CC mayhave a bandwidth of 1.4, 3, 5, 10, 15 or 20 MHz and a maximum of fiveCCs can be aggregated, and therefore, a maximum aggregated bandwidth is100 MHz. In FDD systems, the number of aggregated carriers can bedifferent for DL and UL, where the number of UL CCs is equal to or lowerthan the number of DL component carriers. In some cases, individual CCscan have a different bandwidth than other CCs. In TDD systems, thenumber of CCs as well as the bandwidths of each CC is usually the samefor DL and UL.

CA also comprises individual serving cells to provide individual CCs.The coverage of the serving cells may differ, for example, because CCson different frequency bands will experience different pathloss. Aprimary service cell or PCell may provide a PCC for both UL and DL, andmay handle RRC and NAS related activities. The other serving cells arereferred to as SCells, and each SCell may provide an individual SCC forboth UL and DL. The SCCs may be added and removed as required, whilechanging the PCC may require the UE 2501 to undergo a handover. In LAA,eLAA, and feLAA, some or all of the SCells may operate in the unlicensedspectrum (referred to as “LAA SCells”), and the LAA SCells are assistedby a PCell operating in the licensed spectrum. When a UE is configuredwith more than one LAA SCell, the UE may receive UL grants on theconfigured LAA SCells indicating different PUSCH starting positionswithin a same subframe.

The PDSCH carries user data and higher-layer signaling to the UEs 2501.The PDCCH carries information about the transport format and resourceallocations related to the PDSCH channel, among other things. It mayalso inform the UEs 2501 about the transport format, resourceallocation, and HARQ information related to the uplink shared channel.Typically, downlink scheduling (assigning control and shared channelresource blocks to the UE 2501 b within a cell) may be performed at anyof the RAN nodes 2511 based on channel quality information fed back fromany of the UEs 2501. The downlink resource assignment information may besent on the PDCCH used for (e.g., assigned to) each of the UEs 2501.

The PDCCH uses CCEs to convey the control information. Before beingmapped to resource elements, the PDCCH complex-valued symbols may firstbe organized into quadruplets, which may then be permuted using asub-block interleaver for rate matching. Each PDCCH may be transmittedusing one or more of these CCEs, where each CCE may correspond to ninesets of four physical resource elements known as REGs. Four QuadraturePhase Shift Keying (QPSK) symbols may be mapped to each REG. The PDCCHcan be transmitted using one or more CCEs, depending on the size of theDCI and the channel condition. There can be four or more different PDCCHformats defined in LTE with different numbers of CCEs (e.g., aggregationlevel, L=1, 2, 4, or 8).

Some embodiments may use concepts for resource allocation for controlchannel information that are an extension of the above-describedconcepts. For example, some embodiments may utilize an EPDCCH that usesPDSCH resources for control information transmission. The EPDCCH may betransmitted using one or more ECCEs. Similar to above, each ECCE maycorrespond to nine sets of four physical resource elements known as anEREGs. An ECCE may have other numbers of EREGs in some situations.

The RAN nodes 2511 may be configured to communicate with one another viainterface 2512. In embodiments where the system 2500 is an LTE system(e.g., when CN 2520 is an EPC 2620 as in FIG. 26 ), the interface 2512may be an X2 interface 2512. The X2 interface may be defined between twoor more RAN nodes 2511 (e.g., two or more eNBs and the like) thatconnect to EPC 2520, and/or between two eNBs connecting to EPC 2520. Insome implementations, the X2 interface may include an X2 user planeinterface (X2-U) and an X2 control plane interface (X2-C). The X2-U mayprovide flow control mechanisms for user data packets transferred overthe X2 interface, and may be used to communicate information about thedelivery of user data between eNBs. For example, the X2-U may providespecific sequence number information for user data transferred from aMeNB to an SeNB; information about successful in sequence delivery ofPDCP PDUs to a UE 2501 from an SeNB for user data; information of PDCPPDUs that were not delivered to a UE 2501; information about a currentminimum desired buffer size at the SeNB for transmitting to the UE userdata; and the like. The X2-C may provide intra-LTE access mobilityfunctionality, including context transfers from source to target eNBs,user plane transport control, etc.; load management functionality; aswell as inter-cell interference coordination functionality.

In embodiments where the system 2500 is a 5G or NR system (e.g., when CN2520 is an 5GC 2720 as in FIG. 27 ), the interface 2512 may be an Xninterface 2512. The Xn interface is defined between two or more RANnodes 2511 (e.g., two or more gNBs and the like) that connect to 5GC2520, between a RAN node 2511 (e.g., a gNB) connecting to 5GC 2520 andan eNB, and/or between two eNBs connecting to 5GC 2520. In someimplementations, the Xn interface may include an Xn user plane (Xn-U)interface and an Xn control plane (Xn-C) interface. The Xn-U may providenon-guaranteed delivery of user plane PDUs and support/provide dataforwarding and flow control functionality. The Xn-C may providemanagement and error handling functionality, functionality to manage theXn-C interface; mobility support for UE 2501 in a connected mode (e.g.,CM-CONNECTED) including functionality to manage the UE mobility forconnected mode between one or more RAN nodes 2511. The mobility supportmay include context transfer from an old (source) serving RAN node 2511to new (target) serving RAN node 2511; and control of user plane tunnelsbetween old (source) serving RAN node 2511 to new (target) serving RANnode 2511. A protocol stack of the Xn-U may include a transport networklayer built on Internet Protocol (IP) transport layer, and a GTP-U layeron top of a UDP and/or IP layer(s) to carry user plane PDUs. The Xn-Cprotocol stack may include an application layer signaling protocol(referred to as Xn Application Protocol (Xn-AP)) and a transport networklayer that is built on SCTP. The SCTP may be on top of an IP layer, andmay provide the guaranteed delivery of application layer messages. Inthe transport IP layer, point-to-point transmission is used to deliverthe signaling PDUs. In other implementations, the Xn-U protocol stackand/or the Xn-C protocol stack may be same or similar to the user planeand/or control plane protocol stack(s) shown and described herein.

The RAN 2510 is shown to be communicatively coupled to a core network—inthis embodiment, core network (CN) 2520. The CN 2520 may comprise aplurality of network elements 2522, which are configured to offervarious data and telecommunications services to customers/subscribers(e.g., users of UEs 2501) who are connected to the CN 2520 via the RAN2510. The components of the CN 2520 may be implemented in one physicalnode or separate physical nodes including components to read and executeinstructions from a machine-readable or computer-readable medium (e.g.,a non-transitory machine-readable storage medium). In some embodiments,NFV may be utilized to virtualize any or all of the above-describednetwork node functions via executable instructions stored in one or morecomputer-readable storage mediums (described in further detail below). Alogical instantiation of the CN 2520 may be referred to as a networkslice, and a logical instantiation of a portion of the CN 2520 may bereferred to as a network sub-slice. NFV architectures andinfrastructures may be used to virtualize one or more network functions,alternatively performed by proprietary hardware, onto physical resourcescomprising a combination of industry-standard server hardware, storagehardware, or switches. In other words, NFV systems can be used toexecute virtual or reconfigurable implementations of one or more EPCcomponents/functions.

Generally, the application server 2530 may be an element offeringapplications that use IP bearer resources with the core network (e.g.,UMTS PS domain, LTE PS data services, etc.). The application server 2530can also be configured to support one or more communication services(e.g., VoIP sessions, PTT sessions, group communication sessions, socialnetworking services, etc.) for the UEs 2501 via the EPC 2520.

In embodiments, the CN 2520 may be a 5GC (referred to as “5GC 2520” orthe like), and the RAN 2510 may be connected with the CN 2520 via an NGinterface 2513. In embodiments, the NG interface 2513 may be split intotwo parts, an NG user plane (NG-U) interface 2514, which carries trafficdata between the RAN nodes 2511 and a UPF, and the S1 control plane(NG-C) interface 2515, which is a signaling interface between the RANnodes 2511 and AMFs. Embodiments where the CN 2520 is a 5GC 2520 arediscussed in more detail with regard to FIG. 27 .

In embodiments, the CN 2520 may be a 5G CN (referred to as “5GC 2520” orthe like), while in other embodiments, the CN 2520 may be an EPC). WhereCN 2520 is an EPC (referred to as “EPC 2520” or the like), the RAN 2510may be connected with the CN 2520 via an S1 interface 2513. Inembodiments, the S1 interface 2513 may be split into two parts, an S1user plane (S1-U) interface 2514, which carries traffic data between theRAN nodes 2511 and the S-GW, and the S1-MME interface 2515, which is asignaling interface between the RAN nodes 2511 and MMES.

FIG. 26 illustrates an example architecture of a system 2600 including afirst CN 2620, in accordance with various embodiments. In this example,system 2600 may implement the LTE standard wherein the CN 2620 is an EPC2620 that corresponds with CN XQ20 of Figure XQ. Additionally, the UE2601 may be the same or similar as the UEs XQ01 of Figure XQ, and theE-UTRAN 2610 may be a RAN that is the same or similar to the RAN XQ10 ofFigure XQ, and which may include RAN nodes XQ11 discussed previously.The CN 2620 may comprise MMES 2621, an S-GW 2622, a P-GW 2623, a HSS2624, and a SGSN 2625.

The MMES 2621 may be similar in function to the control plane of legacySGSN, and may implement MM functions to keep track of the currentlocation of a UE 2601. The MMES 2621 may perform various MM proceduresto manage mobility aspects in access such as gateway selection andtracking area list management. MM (also referred to as “EPS MM” or “EMM”in E-UTRAN systems) may refer to all applicable procedures, methods,data storage, etc. that are used to maintain knowledge about a presentlocation of the UE 2601, provide user identity confidentiality, and/orperform other like services to users/subscribers. Each UE 2601 and theMME 2621 may include an MM or EMM sublayer, and an MM context may beestablished in the UE 2601 and the MME 2621 when an attach procedure issuccessfully completed. The MM context may be a data structure ordatabase object that stores MM-related information of the UE 2601. TheMMES 2621 may be coupled with the HSS 2624 via an S6a reference point,coupled with the SGSN 2625 via an S3 reference point, and coupled withthe S-GW 2622 via an S11 reference point.

The SGSN 2625 may be a node that serves the UE 2601 by tracking thelocation of an individual UE 2601 and performing security functions. Inaddition, the SGSN 2625 may perform Inter-EPC node signaling formobility between 2G/3G and E-UTRAN 3GPP access networks; PDN and S-GWselection as specified by the MMEs 2621; handling of UE 2601 time zonefunctions as specified by the MMEs 2621; and MME selection for handoversto E-UTRAN 3GPP access network. The S3 reference point between the MMEs2621 and the SGSN 2625 may enable user and bearer information exchangefor inter-3GPP access network mobility in idle and/or active states.

The HSS 2624 may comprise a database for network users, includingsubscription-related information to support the network entities'handling of communication sessions. The EPC 2620 may comprise one orseveral HSSs 2624, depending on the number of mobile subscribers, on thecapacity of the equipment, on the organization of the network, etc. Forexample, the HSS 2624 can provide support for routing/roaming,authentication, authorization, naming/addressing resolution, locationdependencies, etc. An S6a reference point between the HSS 2624 and theMMEs 2621 may enable transfer of subscription and authentication datafor authenticating/authorizing user access to the EPC 2620 between HSS2624 and the MMEs 2621.

The S-GW 2622 may terminate the S1 interface XQ13 (“S1-U” in FIG. 26 )toward the RAN 2610, and routes data packets between the RAN 2610 andthe EPC 2620. In addition, the S-GW 2622 may be a local mobility anchorpoint for inter-RAN node handovers and also may provide an anchor forinter-3GPP mobility. Other responsibilities may include lawfulintercept, charging, and some policy enforcement. The S11 referencepoint between the S-GW 2622 and the MMEs 2621 may provide a controlplane between the MMEs 2621 and the S-GW 2622. The S-GW 2622 may becoupled with the P-GW 2623 via an S5 reference point.

The P-GW 2623 may terminate an SGi interface toward a PDN 2630. The P-GW2623 may route data packets between the EPC 2620 and external networkssuch as a network including the application server XQ30 (alternativelyreferred to as an “AF”) via an IP interface XQ25 (see e.g., Figure XQ).In embodiments, the P-GW 2623 may be communicatively coupled to anapplication server (application server XQ30 of Figure XQ or PDN 2630 inFIG. 26 ) via an IP communications interface XQ25 (see, e.g., FigureXQ). The S5 reference point between the P-GW 2623 and the S-GW 2622 mayprovide user plane tunneling and tunnel management between the P-GW 2623and the S-GW 2622. The S5 reference point may also be used for S-GW 2622relocation due to UE 2601 mobility and if the S-GW 2622 needs to connectto a non-collocated P-GW 2623 for the required PDN connectivity. TheP-GW 2623 may further include a node for policy enforcement and chargingdata collection (e.g., PCEF (not shown)). Additionally, the SGireference point between the P-GW 2623 and the packet data network (PDN)2630 may be an operator external public, a private PDN, or an intraoperator packet data network, for example, for provision of IMSservices. The P-GW 2623 may be coupled with a PCRF 2626 via a Gxreference point.

PCRF 2626 is the policy and charging control element of the EPC 2620. Ina non-roaming scenario, there may be a single PCRF 2626 in the HomePublic Land Mobile Network (HPLMN) associated with a UE 2601's InternetProtocol Connectivity Access Network (IP-CAN) session. In a roamingscenario with local breakout of traffic, there may be two PCRFsassociated with a UE 2601's IP-CAN session, a Home PCRF (H-PCRF) withinan HPLMN and a Visited PCRF (V-PCRF) within a Visited Public Land MobileNetwork (VPLMN). The PCRF 2626 may be communicatively coupled to theapplication server 2630 via the P-GW 2623. The application server 2630may signal the PCRF 2626 to indicate a new service flow and select theappropriate QoS and charging parameters. The PCRF 2626 may provisionthis rule into a PCEF (not shown) with the appropriate TFT and QCI,which commences the QoS and charging as specified by the applicationserver 2630. The Gx reference point between the PCRF 2626 and the P-GW2623 may allow for the transfer of QoS policy and charging rules fromthe PCRF 2626 to PCEF in the P-GW 2623. An Rx reference point may residebetween the PDN 2630 (or “AF 2630”) and the PCRF 2626.

FIG. 27 illustrates an architecture of a system 2700 including a secondCN 2720 in accordance with various embodiments. The system 2700 is shownto include a UE 2701, which may be the same or similar to the UEs XQ01and UE 2601 discussed previously; a (R)AN 2710, which may be the same orsimilar to the RAN XQ10 and RAN 2610 discussed previously, and which mayinclude RAN nodes XQ11 discussed previously; and a DN 2703, which maybe, for example, operator services, Internet access or 3rd partyservices; and a 5GC 2720. The 5GC 2720 may include an AUSF 2722; an AMF2721; a SMF 2724; a NEF 2723; a PCF 2726; a NRF 2725; a UDM 2727; an AF2728; a UPF 2702; and a NSSF 2729.

The UPF 2702 may act as an anchor point for intra-RAT and inter-RATmobility, an external PDU session point of interconnect to DN 2703, anda branching point to support multi-homed PDU session. The UPF 2702 mayalso perform packet routing and forwarding, perform packet inspection,enforce the user plane part of policy rules, lawfully intercept packets(UP collection), perform traffic usage reporting, perform QoS handlingfor a user plane (e.g., packet filtering, gating, UL/DL rateenforcement), perform Uplink Traffic verification (e.g., SDF to QoS flowmapping), transport level packet marking in the uplink and downlink, andperform downlink packet buffering and downlink data notificationtriggering. UPF 2702 may include an uplink classifier to support routingtraffic flows to a data network. The DN 2703 may represent variousnetwork operator services, Internet access, or third party services. DN2703 may include, or be similar to, application server XQ30 discussedpreviously. The UPF 2702 may interact with the SMF 2724 via an N4reference point between the SMF 2724 and the UPF 2702.

The AUSF 2722 may store data for authentication of UE 2701 and handleauthentication-related functionality. The AUSF 2722 may facilitate acommon authentication framework for various access types. The AUSF 2722may communicate with the AMF 2721 via an N12 reference point between theAMF 2721 and the AUSF 2722; and may communicate with the UDM 2727 via anN13 reference point between the UDM 2727 and the AUSF 2722.Additionally, the AUSF 2722 may exhibit an Nausf service-basedinterface.

The AMF 2721 may be responsible for registration management (e.g., forregistering UE 2701, etc.), connection management, reachabilitymanagement, mobility management, and lawful interception of AMF-relatedevents, and access authentication and authorization. The AMF 2721 may bea termination point for the an N11 reference point between the AMF 2721and the SMF 2724. The AMF 2721 may provide transport for SM messagesbetween the UE 2701 and the SMF 2724, and act as a transparent proxy forrouting SM messages. AMF 2721 may also provide transport for SMSmessages between UE 2701 and an SMSF (not shown by FIG. 27 ). AMF 2721may act as SEAF, which may include interaction with the AUSF 2722 andthe UE 2701, receipt of an intermediate key that was established as aresult of the UE 2701 authentication process. Where USIM basedauthentication is used, the AMF 2721 may retrieve the security materialfrom the AUSF 2722. AMF 2721 may also include a SCM function, whichreceives a key from the SEA that it uses to derive access-networkspecific keys. Furthermore, AMF 2721 may be a termination point of a RANCP interface, which may include or be an N2 reference point between the(R)AN 2710 and the AMF 2721; and the AMF 2721 may be a termination pointof NAS (N1) signalling, and perform NAS ciphering and integrityprotection.

AMF 2721 may also support NAS signalling with a UE 2701 over an N3 IWFinterface. The N3IWF may be used to provide access to untrustedentities. N3IWF may be a termination point for the N2 interface betweenthe (R)AN 2710 and the AMF 2721 for the control plane, and may be atermination point for the N3 reference point between the (R)AN 2710 andthe UPF 2702 for the user plane. As such, the AMF 2721 may handle N2signalling from the SMF 2724 and the AMF 2721 for PDU sessions and QoS,encapsulate/de-encapsulate packets for IPSec and N3 tunnelling, mark N3user-plane packets in the uplink, and enforce QoS corresponding to N3packet marking taking into account QoS requirements associated with suchmarking received over N2. N3IWF may also relay uplink and downlinkcontrol-plane NAS signalling between the UE 2701 and AMF 2721 via an N1reference point between the UE 2701 and the AMF 2721, and relay uplinkand downlink user-plane packets between the UE 2701 and UPF 2702. TheN3IWF also provides mechanisms for IPsec tunnel establishment with theUE 2701. The AMF 2721 may exhibit an Namf service-based interface, andmay be a termination point for an N14 reference point between two AMFs2721 and an N17 reference point between the AMF 2721 and a 5G-EIR (notshown by FIG. 27 ).

The UE 2701 may need to register with the AMF 2721 in order to receivenetwork services. RM is used to register or deregister the UE 2701 withthe network (e.g., AMF 2721), and establish a UE context in the network(e.g., AMF 2721). The UE 2701 may operate in an RM-REGISTERED state oran RM-DEREGISTERED state. In the RM-DEREGISTERED state, the UE 2701 isnot registered with the network, and the UE context in AMF 2721 holds novalid location or routing information for the UE 2701 so the UE 2701 isnot reachable by the AMF 2721. In the RM-REGISTERED state, the UE 2701is registered with the network, and the UE context in AMF 2721 may holda valid location or routing information for the UE 2701 so the UE 2701is reachable by the AMF 2721. In the RM-REGISTERED state, the UE 2701may perform mobility Registration Update procedures, perform periodicRegistration Update procedures triggered by expiration of the periodicupdate timer (e.g., to notify the network that the UE 2701 is stillactive), and perform a Registration Update procedure to update UEcapability information or to re-negotiate protocol parameters with thenetwork, among others.

The AMF 2721 may store one or more RM contexts for the UE 2701, whereeach RM context is associated with a specific access to the network. TheRM context may be a data structure, database object, etc. that indicatesor stores, inter alia, a registration state per access type and theperiodic update timer. The AMF 2721 may also store a 5GC MM context thatmay be the same or similar to the (E)MM context discussed previously. Invarious embodiments, the AMF 2721 may store a CE mode B Restrictionparameter of the UE 2701 in an associated MM context or RM context. TheAMF 2721 may also derive the value, when needed, from the UE's usagesetting parameter already stored in the UE context (and/or MM/RMcontext).

CM may be used to establish and release a signaling connection betweenthe UE 2701 and the AMF 2721 over the N1 interface. The signalingconnection is used to enable NAS signaling exchange between the UE 2701and the CN 2720, and comprises both the signaling connection between theUE and the AN (e.g., RRC connection or UE-N3IWF connection for non-3GPPaccess) and the N2 connection for the UE 2701 between the AN (e.g., RAN2710) and the AMF 2721. The UE 2701 may operate in one of two CM states,CM-IDLE mode or CM-CONNECTED mode. When the UE 2701 is operating in theCM-IDLE state/mode, the UE 2701 may have no NAS signaling connectionestablished with the AMF 2721 over the N1 interface, and there may be(R)AN 2710 signaling connection (e.g., N2 and/or N3 connections) for theUE 2701. When the UE 2701 is operating in the CM-CONNECTED state/mode,the UE 2701 may have an established NAS signaling connection with theAMF 2721 over the N1 interface, and there may be a (R)AN 2710 signalingconnection (e.g., N2 and/or N3 connections) for the UE 2701.Establishment of an N2 connection between the (R)AN 2710 and the AMF2721 may cause the UE 2701 to transition from CM-IDLE mode toCM-CONNECTED mode, and the UE 2701 may transition from the CM-CONNECTEDmode to the CM-IDLE mode when N2 signaling between the (R)AN 2710 andthe AMF 2721 is released.

The SMF 2724 may be responsible for SM (e.g., session establishment,modify and release, including tunnel maintain between UPF and AN node);UE IP address allocation and management (including optionalauthorization); selection and control of UP function; configuringtraffic steering at UPF to route traffic to proper destination;termination of interfaces toward policy control functions; controllingpart of policy enforcement and QoS; lawful intercept (for SM events andinterface to LI system); termination of SM parts of NAS messages;downlink data notification; initiating AN specific SM information, sentvia AMF over N2 to AN; and determining SSC mode of a session. SM mayrefer to management of a PDU session, and a PDU session or “session” mayrefer to a PDU connectivity service that provides or enables theexchange of PDUs between a UE 2701 and a data network (DN) 2703identified by a Data Network Name (DNN). PDU sessions may be establishedupon UE 2701 request, modified upon UE 2701 and 5GC 2720 request, andreleased upon UE 2701 and 5GC 2720 request using NAS SM signalingexchanged over the N1 reference point between the UE 2701 and the SMF2724. Upon request from an application server, the 5GC 2720 may triggera specific application in the UE 2701. In response to receipt of thetrigger message, the UE 2701 may pass the trigger message (or relevantparts/information of the trigger message) to one or more identifiedapplications in the UE 2701. The identified application(s) in the UE2701 may establish a PDU session to a specific DNN. The SMF 2724 maycheck whether the UE 2701 requests are compliant with user subscriptioninformation associated with the UE 2701. In this regard, the SMF 2724may retrieve and/or request to receive update notifications on SMF 2724level subscription data from the UDM 2727.

The SMF 2724 may include the following roaming functionality: handlinglocal enforcement to apply QoS SLAB (VPLMN); charging data collectionand charging interface (VPLMN); lawful intercept (in VPLMN for SM eventsand interface to LI system); and support for interaction with externalDN for transport of signalling for PDU sessionauthorization/authentication by external DN. An N16 reference pointbetween two SMFs 2724 may be included in the system 2700, which may bebetween another SMF 2724 in a visited network and the SMF 2724 in thehome network in roaming scenarios. Additionally, the SMF 2724 mayexhibit the Nsmf service-based interface.

The NEF 2723 may provide means for securely exposing the services andcapabilities provided by 3GPP network functions for third party,internal exposure/re-exposure, Application Functions (e.g., AF 2728),edge computing or fog computing systems, etc. In such embodiments, theNEF 2723 may authenticate, authorize, and/or throttle the AFs. NEF 2723may also translate information exchanged with the AF 2728 andinformation exchanged with internal network functions. For example, theNEF 2723 may translate between an AF-Service-Identifier and an internal5GC information. NEF 2723 may also receive information from othernetwork functions (NFs) based on exposed capabilities of other networkfunctions. This information may be stored at the NEF 2723 as structureddata, or at a data storage NF using standardized interfaces. The storedinformation can then be re-exposed by the NEF 2723 to other NFs and AFs,and/or used for other purposes such as analytics. Additionally, the NEF2723 may exhibit an Nnef service-based interface.

The NRF 2725 may support service discovery functions, receive NFdiscovery requests from NF instances, and provide the information of thediscovered NF instances to the NF instances. NRF 2725 also maintainsinformation of available NF instances and their supported services. Asused herein, the terms “instantiate,” “instantiation,” and the like mayrefer to the creation of an instance, and an “instance” may refer to aconcrete occurrence of an object, which may occur, for example, duringexecution of program code. Additionally, the NRF 2725 may exhibit theNnrf service-based interface.

The PCF 2726 may provide policy rules to control plane function(s) toenforce them, and may also support unified policy framework to governnetwork behaviour. The PCF 2726 may also implement an FE to accesssubscription information relevant for policy decisions in a UDR of theUDM 2727. The PCF 2726 may communicate with the AMF 2721 via an N15reference point between the PCF 2726 and the AMF 2721, which may includea PCF 2726 in a visited network and the AMF 2721 in case of roamingscenarios. The PCF 2726 may communicate with the AF 2728 via an N5reference point between the PCF 2726 and the AF 2728; and with the SMF2724 via an N7 reference point between the PCF 2726 and the SMF 2724.The system 2700 and/or CN 2720 may also include an N24 reference pointbetween the PCF 2726 (in the home network) and a PCF 2726 in a visitednetwork. Additionally, the PCF 2726 may exhibit an Npcf service-basedinterface.

The UDM 2727 may handle subscription-related information to support thenetwork entities' handling of communication sessions, and may storesubscription data of UE 2701. For example, subscription data may becommunicated between the UDM 2727 and the AMF 2721 via an N8 referencepoint between the UDM 2727 and the AMF. The UDM 2727 may include twoparts, an application FE and a UDR (the FE and UDR are not shown by FIG.27 ). The UDR may store subscription data and policy data for the UDM2727 and the PCF 2726, and/or structured data for exposure andapplication data (including PFDs for application detection, applicationrequest information for multiple UEs 2701) for the NEF 2723. The Nudrservice-based interface may be exhibited by the UDR 221 to allow the UDM2727, PCF 2726, and NEF 2723 to access a particular set of the storeddata, as well as to read, update (e.g., add, modify), delete, andsubscribe to notification of relevant data changes in the UDR. The UDMmay include a UDM-FE, which is in charge of processing credentials,location management, subscription management and so on. Severaldifferent front ends may serve the same user in different transactions.The UDM-FE accesses subscription information stored in the UDR andperforms authentication credential processing, user identificationhandling, access authorization, registration/mobility management, andsubscription management. The UDR may interact with the SMF 2724 via anN10 reference point between the UDM 2727 and the SMF 2724. UDM 2727 mayalso support SMS management, wherein an SMS-FE implements the similarapplication logic as discussed previously. Additionally, the UDM 2727may exhibit the Nudm service-based interface.

The AF 2728 may provide application influence on traffic routing,provide access to the NCE, and interact with the policy framework forpolicy control. The NCE may be a mechanism that allows the 5GC 2720 andAF 2728 to provide information to each other via NEF 2723, which may beused for edge computing implementations. In such implementations, thenetwork operator and third party services may be hosted close to the UE2701 access point of attachment to achieve an efficient service deliverythrough the reduced end-to-end latency and load on the transportnetwork. For edge computing implementations, the 5GC may select a UPF2702 close to the UE 2701 and execute traffic steering from the UPF 2702to DN 2703 via the N6 interface. This may be based on the UEsubscription data, UE location, and information provided by the AF 2728.In this way, the AF 2728 may influence UPF (re)selection and trafficrouting. Based on operator deployment, when AF 2728 is considered to bea trusted entity, the network operator may permit AF 2728 to interactdirectly with relevant NFs. Additionally, the AF 2728 may exhibit an Nafservice-based interface.

The NSSF 2729 may select a set of network slice instances serving the UE2701. The NSSF 2729 may also determine allowed NSSAI and the mapping tothe subscribed S-NSSAIs, if needed. The NSSF 2729 may also determine theAMF set to be used to serve the UE 2701, or a list of candidate AMF(s)2721 based on a suitable configuration and possibly by querying the NRF2725. The selection of a set of network slice instances for the UE 2701may be triggered by the AMF 2721 with which the UE 2701 is registered byinteracting with the NSSF 2729, which may lead to a change of AMF 2721.The NSSF 2729 may interact with the AMF 2721 via an N22 reference pointbetween AMF 2721 and NSSF 2729; and may communicate with another NSSF2729 in a visited network via an N31 reference point (not shown by FIG.27 ). Additionally, the NSSF 2729 may exhibit an Nnssf service-basedinterface.

As discussed previously, the CN 2720 may include an SMSF, which may beresponsible for SMS subscription checking and verification, and relayingSM messages to/from the UE 2701 to/from other entities, such as anSMS-GMSC/IWMSC/SMS-router. The SMS may also interact with AMF 2721 andUDM 2727 for a notification procedure that the UE 2701 is available forSMS transfer (e.g., set a UE not reachable flag, and notifying UDM 2727when UE 2701 is available for SMS).

The CN 120 may also include other elements that are not shown by FIG. 27, such as a Data Storage system/architecture, a 5G-EIR, a SEPP, and thelike. The Data Storage system may include a SDSF, an UDSF, and/or thelike. Any NF may store and retrieve unstructured data into/from the UDSF(e.g., UE contexts), via N18 reference point between any NF and the UDSF(not shown by FIG. 27 ). Individual NFs may share a UDSF for storingtheir respective unstructured data or individual NFs may each have theirown UDSF located at or near the individual NFs. Additionally, the UDSFmay exhibit an Nudsf service-based interface (not shown by FIG. 27 ).The 5G-EIR may be an NF that checks the status of PEI for determiningwhether particular equipment/entities are blacklisted from the network;and the SEPP may be a non-transparent proxy that performs topologyhiding, message filtering, and policing on inter-PLMN control planeinterfaces.

Additionally, there may be many more reference points and/orservice-based interfaces between the NF services in the NFs; however,these interfaces and reference points have been omitted from FIG. 27 forclarity. In one example, the CN 2720 may include an Nx interface, whichis an inter-CN interface between the MME (e.g., MME 2621) and the AMF2721 in order to enable interworking between CN 2720 and CN 2620. Otherexample interfaces/reference points may include an N5g-EIR service-basedinterface exhibited by a 5G-EIR, an N27 reference point between the NRFin the visited network and the NRF in the home network; and an N31reference point between the NSSF in the visited network and the NSSF inthe home network.

FIG. 28 illustrates an example of infrastructure equipment 2800 inaccordance with various embodiments. The infrastructure equipment 2800(or “system 2800”) may be implemented as a base station, radio head, RANnode such as the RAN nodes XQ11 and/or AP XQ06 shown and describedpreviously, application server(s) XQ30, and/or any other element/devicediscussed herein. In other examples, the system 2800 could beimplemented in or by a UE.

The system 2800 includes application circuitry 2805, baseband circuitry2810, one or more radio front end modules (RFEMs) 2815, memory circuitry2820, power management integrated circuitry (PMIC) 2825, power teecircuitry 2830, network controller circuitry 2835, network interfaceconnector 2840, satellite positioning circuitry 2845, and user interface2850. In some embodiments, the device 2800 may include additionalelements such as, for example, memory/storage, display, camera, sensor,or input/output (I/O) interface. In other embodiments, the componentsdescribed below may be included in more than one device. For example,said circuitries may be separately included in more than one device forCRAN, vBBU, or other like implementations.

Application circuitry 2805 includes circuitry such as, but not limitedto one or more processors (or processor cores), cache memory, and one ormore of low drop-out voltage regulators (LDOs), interrupt controllers,serial interfaces such as SPI, I2C or universal programmable serialinterface module, real time clock (RTC), timer-counters includinginterval and watchdog timers, general purpose input/output (I/O or IO),memory card controllers such as Secure Digital (SD) MultiMediaCard (MMC)or similar, Universal Serial Bus (USB) interfaces, Mobile IndustryProcessor Interface (MIPI) interfaces and Joint Test Access Group (JTAG)test access ports. The processors (or cores) of the applicationcircuitry 2805 may be coupled with or may include memory/storageelements and may be configured to execute instructions stored in thememory/storage to enable various applications or operating systems torun on the system 2800. In some implementations, the memory/storageelements may be on-chip memory circuitry, which may include any suitablevolatile and/or non-volatile memory, such as DRAM, SRAM, EPROM, EEPROM,Flash memory, solid-state memory, and/or any other type of memory devicetechnology, such as those discussed herein.

The processor(s) of application circuitry 2805 may include, for example,one or more processor cores (CPUs), one or more application processors,one or more graphics processing units (GPUs), one or more reducedinstruction set computing (RISC) processors, one or more Acorn RISCMachine (ARM) processors, one or more complex instruction set computing(CISC) processors, one or more digital signal processors (DSP), one ormore FPGAs, one or more PLDs, one or more ASICs, one or moremicroprocessors or controllers, or any suitable combination thereof. Insome embodiments, the application circuitry 2805 may comprise, or maybe, a special-purpose processor/controller to operate according to thevarious embodiments herein. As examples, the processor(s) of applicationcircuitry 2805 may include one or more Intel Pentium®, Core®, or Xeon®processor(s); Advanced Micro Devices (AMD) Ryzen® processor(s),Accelerated Processing Units (APUs), or Epyc® processors; ARM-basedprocessor(s) licensed from ARM Holdings, Ltd. such as the ARM Cortex-Afamily of processors and the ThunderX2® provided by Cavium™, Inc.; aMIPS-based design from MIPS Technologies, Inc. such as MIPS WarriorP-class processors; and/or the like. In some embodiments, the system2800 may not utilize application circuitry 2805, and instead may includea special-purpose processor/controller to process IP data received froman EPC or 5GC, for example.

In some implementations, the application circuitry 2805 may include oneor more hardware accelerators, which may be microprocessors,programmable processing devices, or the like. The one or more hardwareaccelerators may include, for example, computer vision (CV) and/or deeplearning (DL) accelerators. As examples, the programmable processingdevices may be one or more a field-programmable devices (FPDs) such asfield-programmable gate arrays (FPGAs) and the like; programmable logicdevices (PLDs) such as complex PLDs (CPLDs), high-capacity PLDs(HCPLDs), and the like; ASICs such as structured ASICs and the like;programmable SoCs (PSoCs); and the like. In such implementations, thecircuitry of application circuitry 2805 may comprise logic blocks orlogic fabric, and other interconnected resources that may be programmedto perform various functions, such as the procedures, methods,functions, etc. of the various embodiments discussed herein. In suchembodiments, the circuitry of application circuitry 2805 may includememory cells (e.g., erasable programmable read-only memory (EPROM),electrically erasable programmable read-only memory (EEPROM), flashmemory, static memory (e.g., static random access memory (SRAM),anti-fuses, etc.)) used to store logic blocks, logic fabric, data, etc.in look-up-tables (LUTs) and the like.

The baseband circuitry 2810 may be implemented, for example, as asolder-down substrate including one or more integrated circuits, asingle packaged integrated circuit soldered to a main circuit board or amulti-chip module containing two or more integrated circuits. Thevarious hardware electronic elements of baseband circuitry 2810 arediscussed infra with regard to FIG. 30 .

User interface circuitry 2850 may include one or more user interfacesdesigned to enable user interaction with the system 2800 or peripheralcomponent interfaces designed to enable peripheral component interactionwith the system 2800. User interfaces may include, but are not limitedto, one or more physical or virtual buttons (e.g., a reset button), oneor more indicators (e.g., light emitting diodes (LEDs)), a physicalkeyboard or keypad, a mouse, a touchpad, a touchscreen, speakers orother audio emitting devices, microphones, a printer, a scanner, aheadset, a display screen or display device, etc. Peripheral componentinterfaces may include, but are not limited to, a nonvolatile memoryport, a universal serial bus (USB) port, an audio jack, a power supplyinterface, etc.

The radio front end modules (RFEMs) 2815 may comprise a millimeter wave(mmWave) RFEM and one or more sub-mmWave radio frequency integratedcircuits (RFICs). In some implementations, the one or more sub-mmWaveRFICs may be physically separated from the mmWave RFEM. The RFICs mayinclude connections to one or more antennas or antenna arrays (see e.g.,antenna array 3011 of FIG. 30 infra), and the RFEM may be connected tomultiple antennas. In alternative implementations, both mmWave andsub-mmWave radio functions may be implemented in the same physical RFEM2815, which incorporates both mmWave antennas and sub-mmWave.

The memory circuitry 2820 may include one or more of volatile memoryincluding dynamic random access memory (DRAM) and/or synchronous dynamicrandom access memory (SDRAM), and nonvolatile memory (NVM) includinghigh-speed electrically erasable memory (commonly referred to as Flashmemory), phase change random access memory (PRAM), magnetoresistiverandom access memory (MRAM), etc., and may incorporate thethree-dimensional (3D) cross-point (XPOINT) memories from Intel® andMicron®. Memory circuitry 2820 may be implemented as one or more ofsolder down packaged integrated circuits, socketed memory modules andplug-in memory cards.

The PMIC 2825 may include voltage regulators, surge protectors, poweralarm detection circuitry, and one or more backup power sources such asa battery or capacitor. The power alarm detection circuitry may detectone or more of brown out (under-voltage) and surge (over-voltage)conditions. The power tee circuitry 2830 may provide for electricalpower drawn from a network cable to provide both power supply and dataconnectivity to the infrastructure equipment 2800 using a single cable.

The network controller circuitry 2835 may provide connectivity to anetwork using a standard network interface protocol such as Ethernet,Ethernet over GRE Tunnels, Ethernet over Multiprotocol Label Switching(MPLS), or some other suitable protocol. Network connectivity may beprovided to/from the infrastructure equipment 2800 via network interfaceconnector 2840 using a physical connection, which may be electrical(commonly referred to as a “copper interconnect”), optical, or wireless.The network controller circuitry 2835 may include one or more dedicatedprocessors and/or FPGAs to communicate using one or more of theaforementioned protocols. In some implementations, the networkcontroller circuitry 2835 may include multiple controllers to provideconnectivity to other networks using the same or different protocols.

The positioning circuitry 2845 includes circuitry to receive and decodesignals transmitted/broadcasted by a positioning network of a globalnavigation satellite system (GNSS). Examples of navigation satelliteconstellations (or GNSS) include United States' Global PositioningSystem (GPS), Russia's Global Navigation System (GLONASS), the EuropeanUnion's Galileo system, China's BeiDou Navigation Satellite System, aregional navigation system or GNSS augmentation system (e.g., Navigationwith Indian Constellation (NAVIC), Japan's Quasi-Zenith Satellite System(QZSS), France's Doppler Orbitography and Radio-positioning Integratedby Satellite (DORIS), etc.), or the like. The positioning circuitry 2845comprises various hardware elements (e.g., including hardware devicessuch as switches, filters, amplifiers, antenna elements, and the like tofacilitate OTA communications) to communicate with components of apositioning network, such as navigation satellite constellation nodes.In some embodiments, the positioning circuitry 2845 may include aMicro-Technology for Positioning, Navigation, and Timing (Micro-PNT) ICthat uses a master timing clock to perform position tracking/estimationwithout GNSS assistance. The positioning circuitry 2845 may also be partof, or interact with, the baseband circuitry 2810 and/or RFEMs 2815 tocommunicate with the nodes and components of the positioning network.The positioning circuitry 2845 may also provide position data and/ortime data to the application circuitry 2805, which may use the data tosynchronize operations with various infrastructure (e.g., RAN nodesXQ11, etc.), or the like.

The components shown by FIG. 28 may communicate with one another usinginterface circuitry, which may include any number of bus and/orinterconnect (IX) technologies such as industry standard architecture(ISA), extended ISA (EISA), peripheral component interconnect (PCI),peripheral component interconnect extended (PCIx), PCI express (PCIe),or any number of other technologies. The bus/IX may be a proprietarybus, for example, used in a SoC based system. Other bus/IX systems maybe included, such as an I2C interface, an SPI interface, point to pointinterfaces, and a power bus, among others.

FIG. 29 illustrates an example of a platform 2900 (or “device 2900”) inaccordance with various embodiments. In embodiments, the computerplatform 2900 may be suitable for use as UEs XQ01, 2601, 2701,application servers XQ30, and/or any other element/device discussedherein. The platform 2900 may include any combinations of the componentsshown in the example. The components of platform 2900 may be implementedas integrated circuits (ICs), portions thereof, discrete electronicdevices, or other modules, logic, hardware, software, firmware, or acombination thereof adapted in the computer platform 2900, or ascomponents otherwise incorporated within a chassis of a larger system.The block diagram of FIG. 29 is intended to show a high level view ofcomponents of the computer platform 2900. However, some of thecomponents shown may be omitted, additional components may be present,and different arrangement of the components shown may occur in otherimplementations.

Application circuitry 2905 includes circuitry such as, but not limitedto one or more processors (or processor cores), cache memory, and one ormore of LDOs, interrupt controllers, serial interfaces such as SPI, I2Cor universal programmable serial interface module, RTC, timer-countersincluding interval and watchdog timers, general purpose I/O, memory cardcontrollers such as SD MMC or similar, USB interfaces, MIPI interfaces,and JTAG test access ports. The processors (or cores) of the applicationcircuitry 2905 may be coupled with or may include memory/storageelements and may be configured to execute instructions stored in thememory/storage to enable various applications or operating systems torun on the system 2900. In some implementations, the memory/storageelements may be on-chip memory circuitry, which may include any suitablevolatile and/or non-volatile memory, such as DRAM, SRAM, EPROM, EEPROM,Flash memory, solid-state memory, and/or any other type of memory devicetechnology, such as those discussed herein.

The processor(s) of application circuitry 2805 may include, for example,one or more processor cores, one or more application processors, one ormore GPUs, one or more RISC processors, one or more ARM processors, oneor more CISC processors, one or more DSP, one or more FPGAs, one or morePLDs, one or more ASICs, one or more microprocessors or controllers, amultithreaded processor, an ultra-low voltage processor, an embeddedprocessor, some other known processing element, or any suitablecombination thereof. In some embodiments, the application circuitry 2805may comprise, or may be, a special-purpose processor/controller tooperate according to the various embodiments herein.

As examples, the processor(s) of application circuitry 2905 may includean Intel® Architecture Core™ based processor, such as a Quark™, anAtom™, an i3, an i5, an i7, or an MCU-class processor, or another suchprocessor available from Intel® Corporation, Santa Clara, Calif. Theprocessors of the application circuitry 2905 may also be one or more ofAdvanced Micro Devices (AMD) Ryzen® processor(s) or AcceleratedProcessing Units (APUs); A5-A9 processor(s) from Apple® Inc.,Snapdragon™ processor(s) from Qualcomm® Technologies, Inc., TexasInstruments, Inc.® Open Multimedia Applications Platform (OMAP)™processor(s); a MIPS-based design from MIPS Technologies, Inc. such asMIPS Warrior M-class, Warrior I-class, and Warrior P-class processors;an ARM-based design licensed from ARM Holdings, Ltd., such as the ARMCortex-A, Cortex-R, and Cortex-M family of processors; or the like. Insome implementations, the application circuitry 2905 may be a part of asystem on a chip (SoC) in which the application circuitry 2905 and othercomponents are formed into a single integrated circuit, or a singlepackage, such as the Edison™ or Galileo™ SoC boards from Intel®Corporation.

Additionally or alternatively, application circuitry 2905 may includecircuitry such as, but not limited to, one or more a field-programmabledevices (FPDs) such as FPGAs and the like; programmable logic devices(PLDs) such as complex PLDs (CPLDs), high-capacity PLDs (HCPLDs), andthe like; ASICs such as structured ASICs and the like; programmable SoCs(PSoCs); and the like. In such embodiments, the circuitry of applicationcircuitry 2905 may comprise logic blocks or logic fabric, and otherinterconnected resources that may be programmed to perform variousfunctions, such as the procedures, methods, functions, etc. of thevarious embodiments discussed herein. In such embodiments, the circuitryof application circuitry 2905 may include memory cells (e.g., erasableprogrammable read-only memory (EPROM), electrically erasableprogrammable read-only memory (EEPROM), flash memory, static memory(e.g., static random access memory (SRAM), anti-fuses, etc.)) used tostore logic blocks, logic fabric, data, etc. in look-up tables (LUTs)and the like.

The baseband circuitry 2910 may be implemented, for example, as asolder-down substrate including one or more integrated circuits, asingle packaged integrated circuit soldered to a main circuit board or amulti-chip module containing two or more integrated circuits. Thevarious hardware electronic elements of baseband circuitry 2910 arediscussed infra with regard to FIG. 30 .

The RFEMs 2915 may comprise a millimeter wave (mmWave) RFEM and one ormore sub-mmWave radio frequency integrated circuits (RFICs). In someimplementations, the one or more sub-mmWave RFICs may be physicallyseparated from the mmWave RFEM. The RFICs may include connections to oneor more antennas or antenna arrays (see e.g., antenna array 3011 of FIG.30 infra), and the RFEM may be connected to multiple antennas. Inalternative implementations, both mmWave and sub-mmWave radio functionsmay be implemented in the same physical RFEM 2915, which incorporatesboth mmWave antennas and sub-mmWave.

The memory circuitry 2920 may include any number and type of memorydevices used to provide for a given amount of system memory. Asexamples, the memory circuitry 2920 may include one or more of volatilememory including random access memory (RAM), dynamic RAM (DRAM) and/orsynchronous dynamic RAM (SDRAM), and nonvolatile memory (NVM) includinghigh-speed electrically erasable memory (commonly referred to as Flashmemory), phase change random access memory (PRAM), magnetoresistiverandom access memory (MRAM), etc. The memory circuitry 2920 may bedeveloped in accordance with a Joint Electron Devices EngineeringCouncil (JEDEC) low power double data rate (LPDDR)-based design, such asLPDDR2, LPDDR3, LPDDR4, or the like. Memory circuitry 2920 may beimplemented as one or more of solder down packaged integrated circuits,single die package (SDP), dual die package (DDP) or quad die package(Q17P), socketed memory modules, dual inline memory modules (DIMMs)including microDIMMs or MiniDIMMs, and/or soldered onto a motherboardvia a ball grid array (BGA). In low power implementations, the memorycircuitry 2920 may be on-die memory or registers associated with theapplication circuitry 2905. To provide for persistent storage ofinformation such as data, applications, operating systems and so forth,memory circuitry 2920 may include one or more mass storage devices,which may include, inter alia, a solid state disk drive (SSDD), harddisk drive (HDD), a micro HDD, resistance change memories, phase changememories, holographic memories, or chemical memories, among others. Forexample, the computer platform 2900 may incorporate thethree-dimensional (3D) cross-point (XPOINT) memories from Intel® andMicron®.

Removable memory circuitry 2923 may include devices, circuitry,enclosures/housings, ports or receptacles, etc. used to couple portabledata storage devices with the platform 2900. These portable data storagedevices may be used for mass storage purposes, and may include, forexample, flash memory cards (e.g., Secure Digital (SD) cards, microSDcards, xD picture cards, and the like), and USB flash drives, opticaldiscs, external HDDs, and the like.

The platform 2900 may also include interface circuitry (not shown) thatis used to connect external devices with the platform 2900. The externaldevices connected to the platform 2900 via the interface circuitryinclude sensor circuitry 2921 and electro-mechanical components (EMCs)2922, as well as removable memory devices coupled to removable memorycircuitry 2923.

The sensor circuitry 2921 include devices, modules, or subsystems whosepurpose is to detect events or changes in its environment and send theinformation (sensor data) about the detected events to some other adevice, module, subsystem, etc. Examples of such sensors include, interalia, inertia measurement units (IMUs) comprising accelerometers,gyroscopes, and/or magnetometers; microelectromechanical systems (MEMS)or nanoelectromechanical systems (NEMS) comprising 3-axisaccelerometers, 3-axis gyroscopes, and/or magnetometers; level sensors;flow sensors; temperature sensors (e.g., thermistors); pressure sensors;barometric pressure sensors; gravimeters; altimeters; image capturedevices (e.g., cameras or lensless apertures); light detection andranging (LiDAR) sensors; proximity sensors (e.g., infrared radiationdetector and the like), depth sensors, ambient light sensors, ultrasonictransceivers; microphones or other like audio capture devices; etc.

EMCs 2922 include devices, modules, or subsystems whose purpose is toenable platform 2900 to change its state, position, and/or orientation,or move or control a mechanism or (sub)system. Additionally, EMCs 2922may be configured to generate and send messages/signalling to othercomponents of the platform 2900 to indicate a current state of the EMCs2922. Examples of the EMCs 2922 include one or more power switches,relays including electromechanical relays (EMRs) and/or solid staterelays (SSRs), actuators (e.g., valve actuators, etc.), an audible soundgenerator, a visual warning device, motors (e.g., DC motors, steppermotors, etc.), wheels, thrusters, propellers, claws, clamps, hooks,and/or other like electro-mechanical components. In embodiments,platform 2900 is configured to operate one or more EMCs 2922 based onone or more captured events and/or instructions or control signalsreceived from a service provider and/or various clients.

In some implementations, the interface circuitry may connect theplatform 2900 with positioning circuitry 2945. The positioning circuitry2945 includes circuitry to receive and decode signalstransmitted/broadcasted by a positioning network of a GNSS. Examples ofnavigation satellite constellations (or GNSS) include United States'GPS, Russia's GLONASS, the European Union's Galileo system, China'sBeiDou Navigation Satellite System, a regional navigation system or GNSSaugmentation system (e.g., NAVIC), Japan's QZSS, France's DORIS, etc.),or the like. The positioning circuitry 2945 comprises various hardwareelements (e.g., including hardware devices such as switches, filters,amplifiers, antenna elements, and the like to facilitate OTAcommunications) to communicate with components of a positioning network,such as navigation satellite constellation nodes. In some embodiments,the positioning circuitry 2945 may include a Micro-PNT IC that uses amaster timing clock to perform position tracking/estimation without GNSSassistance. The positioning circuitry 2945 may also be part of, orinteract with, the baseband circuitry 2810 and/or RFEMs 2915 tocommunicate with the nodes and components of the positioning network.The positioning circuitry 2945 may also provide position data and/ortime data to the application circuitry 2905, which may use the data tosynchronize operations with various infrastructure (e.g., radio basestations), for turn-by-turn navigation applications, or the like

In some implementations, the interface circuitry may connect theplatform 2900 with Near-Field Communication (NFC) circuitry 2940. NFCcircuitry 2940 is configured to provide contactless, short-rangecommunications based on radio frequency identification (RFID) standards,wherein magnetic field induction is used to enable communication betweenNFC circuitry 2940 and NFC-enabled devices external to the platform 2900(e.g., an “NFC touchpoint”). NFC circuitry 2940 comprises an NFCcontroller coupled with an antenna element and a processor coupled withthe NFC controller. The NFC controller may be a chip/IC providing NFCfunctionalities to the NFC circuitry 2940 by executing NFC controllerfirmware and an NFC stack. The NFC stack may be executed by theprocessor to control the NFC controller, and the NFC controller firmwaremay be executed by the NFC controller to control the antenna element toemit short-range RF signals. The RF signals may power a passive NFC tag(e.g., a microchip embedded in a sticker or wristband) to transmitstored data to the NFC circuitry 2940, or initiate data transfer betweenthe NFC circuitry 2940 and another active NFC device (e.g., a smartphoneor an NFC-enabled POS terminal) that is proximate to the platform 2900.

The driver circuitry 2946 may include software and hardware elementsthat operate to control particular devices that are embedded in theplatform 2900, attached to the platform 2900, or otherwisecommunicatively coupled with the platform 2900. The driver circuitry2946 may include individual drivers allowing other components of theplatform 2900 to interact with or control various input/output (I/O)devices that may be present within, or connected to, the platform 2900.For example, driver circuitry 2946 may include a display driver tocontrol and allow access to a display device, a touchscreen driver tocontrol and allow access to a touchscreen interface of the platform2900, sensor drivers to obtain sensor readings of sensor circuitry 2921and control and allow access to sensor circuitry 2921, EMC drivers toobtain actuator positions of the EMCs 2922 and/or control and allowaccess to the EMCs 2922, a camera driver to control and allow access toan embedded image capture device, audio drivers to control and allowaccess to one or more audio devices.

The power management integrated circuitry (PMIC) 2925 (also referred toas “power management circuitry 2925”) may manage power provided tovarious components of the platform 2900. In particular, with respect tothe baseband circuitry 2910, the PMIC 2925 may control power-sourceselection, voltage scaling, battery charging, or DC-to-DC conversion.The PMIC 2925 may often be included when the platform 2900 is capable ofbeing powered by a battery 2930, for example, when the device isincluded in a UE XQ01, 2601, 2701.

In some embodiments, the PMIC 2925 may control, or otherwise be part of,various power saving mechanisms of the platform 2900. For example, ifthe platform 2900 is in an RRC_Connected state, where it is stillconnected to the RAN node as it expects to receive traffic shortly, thenit may enter a state known as Discontinuous Reception Mode (DRX) after aperiod of inactivity. During this state, the platform 2900 may powerdown for brief intervals of time and thus save power. If there is nodata traffic activity for an extended period of time, then the platform2900 may transition off to an RRC Idle state, where it disconnects fromthe network and does not perform operations such as channel qualityfeedback, handover, etc. The platform 2900 goes into a very low powerstate and it performs paging where again it periodically wakes up tolisten to the network and then powers down again. The platform 2900 maynot receive data in this state; in order to receive data, it musttransition back to RRC_Connected state. An additional power saving modemay allow a device to be unavailable to the network for periods longerthan a paging interval (ranging from seconds to a few hours). Duringthis time, the device is totally unreachable to the network and maypower down completely. Any data sent during this time incurs a largedelay and it is assumed the delay is acceptable.

A battery 2930 may power the platform 2900, although in some examplesthe platform 2900 may be mounted deployed in a fixed location, and mayhave a power supply coupled to an electrical grid. The battery 2930 maybe a lithium ion battery, a metal-air battery, such as a zinc-airbattery, an aluminum-air battery, a lithium-air battery, and the like.In some implementations, such as in V2X applications, the battery 2930may be a typical lead-acid automotive battery.

In some implementations, the battery 2930 may be a “smart battery,”which includes or is coupled with a Battery Management System (BMS) orbattery monitoring integrated circuitry. The BMS may be included in theplatform 2900 to track the state of charge (SoCh) of the battery 2930.The BMS may be used to monitor other parameters of the battery 2930 toprovide failure predictions, such as the state of health (SoH) and thestate of function (SoF) of the battery 2930. The BMS may communicate theinformation of the battery 2930 to the application circuitry 2905 orother components of the platform 2900. The BMS may also include ananalog-to-digital (ADC) convertor that allows the application circuitry2905 to directly monitor the voltage of the battery 2930 or the currentflow from the battery 2930. The battery parameters may be used todetermine actions that the platform 2900 may perform, such astransmission frequency, network operation, sensing frequency, and thelike.

A power block, or other power supply coupled to an electrical grid maybe coupled with the BMS to charge the battery 2930. In some examples,the power block XS30 may be replaced with a wireless power receiver toobtain the power wirelessly, for example, through a loop antenna in thecomputer platform 2900. In these examples, a wireless battery chargingcircuit may be included in the BMS. The specific charging circuitschosen may depend on the size of the battery 2930, and thus, the currentrequired. The charging may be performed using the Airfuel standardpromulgated by the Airfuel Alliance, the Qi wireless charging standardpromulgated by the Wireless Power Consortium, or the Rezence chargingstandard promulgated by the Alliance for Wireless Power, among others.

User interface circuitry 2950 includes various input/output (I/O)devices present within, or connected to, the platform 2900, and includesone or more user interfaces designed to enable user interaction with theplatform 2900 and/or peripheral component interfaces designed to enableperipheral component interaction with the platform 2900. The userinterface circuitry 2950 includes input device circuitry and outputdevice circuitry. Input device circuitry includes any physical orvirtual means for accepting an input including, inter alia, one or morephysical or virtual buttons (e.g., a reset button), a physical keyboard,keypad, mouse, touchpad, touchscreen, microphones, scanner, headset,and/or the like. The output device circuitry includes any physical orvirtual means for showing information or otherwise conveyinginformation, such as sensor readings, actuator position(s), or otherlike information. Output device circuitry may include any number and/orcombinations of audio or visual display, including, inter alia, one ormore simple visual outputs/indicators (e.g., binary status indicators(e.g., light emitting diodes (LEDs)) and multi-character visual outputs,or more complex outputs such as display devices or touchscreens (e.g.,Liquid Chrystal Displays (LCD), LED displays, quantum dot displays,projectors, etc.), with the output of characters, graphics, multimediaobjects, and the like being generated or produced from the operation ofthe platform 2900. The output device circuitry may also include speakersor other audio emitting devices, printer(s), and/or the like. In someembodiments, the sensor circuitry 2921 may be used as the input devicecircuitry (e.g., an image capture device, motion capture device, or thelike) and one or more EMCs may be used as the output device circuitry(e.g., an actuator to provide haptic feedback or the like). In anotherexample, NFC circuitry comprising an NFC controller coupled with anantenna element and a processing device may be included to readelectronic tags and/or connect with another NFC-enabled device.Peripheral component interfaces may include, but are not limited to, anon-volatile memory port, a USB port, an audio jack, a power supplyinterface, etc.

Although not shown, the components of platform 2900 may communicate withone another using a suitable bus or interconnect (IX) technology, whichmay include any number of technologies, including ISA, EISA, PCI, PCIx,PCIe, a Time-Trigger Protocol (TTP) system, a FlexRay system, or anynumber of other technologies. The bus/IX may be a proprietary bus/IX,for example, used in a SoC based system. Other bus/IX systems may beincluded, such as an I2C interface, an SPI interface, point-to-pointinterfaces, and a power bus, among others.

FIG. 30 illustrates example components of baseband circuitry 3010 andradio front end modules (RFEM) 3015 in accordance with variousembodiments. The baseband circuitry 3010 corresponds to the basebandcircuitry 2810 and 2910 of FIGS. 28 and 29 , respectively. The RFEM 3015corresponds to the RFEM 2815 and 2915 of FIGS. 28 and 29 , respectively.As shown, the RFEMs 3015 may include Radio Frequency (RF) circuitry3006, front-end module (FEM) circuitry 3008, antenna array 3011 coupledtogether at least as shown.

The baseband circuitry 3010 includes circuitry and/or control logicconfigured to carry out various radio/network protocol and radio controlfunctions that enable communication with one or more radio networks viathe RF circuitry 3006. The radio control functions may include, but arenot limited to, signal modulation/demodulation, encoding/decoding, radiofrequency shifting, etc. In some embodiments, modulation/demodulationcircuitry of the baseband circuitry 3010 may include Fast-FourierTransform (FFT), precoding, or constellation mapping/demappingfunctionality. In some embodiments, encoding/decoding circuitry of thebaseband circuitry 3010 may include convolution, tail-bitingconvolution, turbo, Viterbi, or Low Density Parity Check (LDPC)encoder/decoder functionality. Embodiments of modulation/demodulationand encoder/decoder functionality are not limited to these examples andmay include other suitable functionality in other embodiments. Thebaseband circuitry 3010 is configured to process baseband signalsreceived from a receive signal path of the RF circuitry 3006 and togenerate baseband signals for a transmit signal path of the RF circuitry3006. The baseband circuitry 3010 is configured to interface withapplication circuitry 2805/2905 (see FIGS. 28 and 29 ) for generationand processing of the baseband signals and for controlling operations ofthe RF circuitry 3006. The baseband circuitry 3010 may handle variousradio control functions.

The aforementioned circuitry and/or control logic of the basebandcircuitry 3010 may include one or more single or multi-core processors.For example, the one or more processors may include a 3G basebandprocessor 3004A, a 4G/LTE baseband processor 3004B, a 5G/NR basebandprocessor 3004C, or some other baseband processor(s) 3004D for otherexisting generations, generations in development or to be developed inthe future (e.g., sixth generation (6G), etc.). In other embodiments,some or all of the functionality of baseband processors 3004A-D may beincluded in modules stored in the memory 3004G and executed via aCentral Processing Unit (CPU) 3004E. In other embodiments, some or allof the functionality of baseband processors 3004A-D may be provided ashardware accelerators (e.g., FPGAs, ASICs, etc.) loaded with theappropriate bit streams or logic blocks stored in respective memorycells. In various embodiments, the memory 3004G may store program codeof a real-time OS (RTOS), which when executed by the CPU 3004E (or otherbaseband processor), is to cause the CPU 3004E (or other basebandprocessor) to manage resources of the baseband circuitry 3010, scheduletasks, etc. Examples of the RTOS may include Operating System Embedded(OSE)™ provided by Enea®, Nucleus RTOS™ provided by Mentor Graphics®,Versatile Real-Time Executive (VRTX) provided by Mentor Graphics®,ThreadX™ provided by Express Logic®, FreeRTOS, REX OS provided byQualcomm®, OKL4 provided by Open Kernel (OK) Labs®, or any othersuitable RTOS, such as those discussed herein. In addition, the basebandcircuitry 3010 includes one or more audio digital signal processor(s)(DSP) 3004F. The audio DSP(s) 3004F include elements forcompression/decompression and echo cancellation and may include othersuitable processing elements in other embodiments.

In some embodiments, each of the processors 3004A-3004E includerespective memory interfaces to send/receive data to/from the memory3004G. The baseband circuitry 3010 may further include one or moreinterfaces to communicatively couple to other circuitries/devices, suchas an interface to send/receive data to/from memory external to thebaseband circuitry 3010; an application circuitry interface tosend/receive data to/from the application circuitry 2805/2905 of FIGS.28 -XT); an RF circuitry interface to send/receive data to/from RFcircuitry 3006 of FIG. 30 ; a wireless hardware connectivity interfaceto send/receive data to/from one or more wireless hardware elements(e.g., Near Field Communication (NFC) components, Bluetooth®/Bluetooth®Low Energy components, Wi-Fi® components, and/or the like); and a powermanagement interface to send/receive power or control signals to/fromthe PMIC 2925.

In alternate embodiments (which may be combined with the above describedembodiments), baseband circuitry 3010 comprises one or more digitalbaseband systems, which are coupled with one another via an interconnectsubsystem and to a CPU subsystem, an audio subsystem, and an interfacesubsystem. The digital baseband subsystems may also be coupled to adigital baseband interface and a mixed-signal baseband subsystem viaanother interconnect subsystem. Each of the interconnect subsystems mayinclude a bus system, point-to-point connections, network-on-chip (NOC)structures, and/or some other suitable bus or interconnect technology,such as those discussed herein. The audio subsystem may include DSPcircuitry, buffer memory, program memory, speech processing acceleratorcircuitry, data converter circuitry such as analog-to-digital anddigital-to-analog converter circuitry, analog circuitry including one ormore of amplifiers and filters, and/or other like components. In anaspect of the present disclosure, baseband circuitry 3010 may includeprotocol processing circuitry with one or more instances of controlcircuitry (not shown) to provide control functions for the digitalbaseband circuitry and/or radio frequency circuitry (e.g., the radiofront end modules 3015).

Although not shown by FIG. 30 , in some embodiments, the basebandcircuitry 3010 includes individual processing device(s) to operate oneor more wireless communication protocols (e.g., a “multi-protocolbaseband processor” or “protocol processing circuitry”) and individualprocessing device(s) to implement PHY layer functions. In theseembodiments, the PHY layer functions include the aforementioned radiocontrol functions. In these embodiments, the protocol processingcircuitry operates or implements various protocol layers/entities of oneor more wireless communication protocols. In a first example, theprotocol processing circuitry may operate LTE protocol entities and/or5G/NR protocol entities when the baseband circuitry 3010 and/or RFcircuitry 3006 are part of mmWave communication circuitry or some othersuitable cellular communication circuitry. In the first example, theprotocol processing circuitry would operate MAC, RLC, PDCP, SDAP, RRC,and NAS functions. In a second example, the protocol processingcircuitry may operate one or more IEEE-based protocols when the basebandcircuitry 3010 and/or RF circuitry 3006 are part of a Wi-Ficommunication system. In the second example, the protocol processingcircuitry would operate Wi-Fi MAC and logical link control (LLC)functions. The protocol processing circuitry may include one or morememory structures (e.g., 3004G) to store program code and data foroperating the protocol functions, as well as one or more processingcores to execute the program code and perform various operations usingthe data. The baseband circuitry 3010 may also support radiocommunications for more than one wireless protocol.

The various hardware elements of the baseband circuitry 3010 discussedherein may be implemented, for example, as a solder-down substrateincluding one or more integrated circuits (ICs), a single packaged ICsoldered to a main circuit board or a multi-chip module containing twoor more ICs. In one example, the components of the baseband circuitry3010 may be suitably combined in a single chip or chipset, or disposedon a same circuit board. In another example, some or all of theconstituent components of the baseband circuitry 3010 and RF circuitry3006 may be implemented together such as, for example, a system on achip (SoC) or System-in-Package (SiP). In another example, some or allof the constituent components of the baseband circuitry 3010 may beimplemented as a separate SoC that is communicatively coupled with andRF circuitry 3006 (or multiple instances of RF circuitry 3006). In yetanother example, some or all of the constituent components of thebaseband circuitry 3010 and the application circuitry 2805/2905 may beimplemented together as individual SoCs mounted to a same circuit board(e.g., a “multi-chip package”).

In some embodiments, the baseband circuitry 3010 may provide forcommunication compatible with one or more radio technologies. Forexample, in some embodiments, the baseband circuitry 3010 may supportcommunication with an E-UTRAN or other WMAN, a WLAN, a WPAN. Embodimentsin which the baseband circuitry 3010 is configured to support radiocommunications of more than one wireless protocol may be referred to asmulti-mode baseband circuitry.

RF circuitry 3006 may enable communication with wireless networks usingmodulated electromagnetic radiation through a non-solid medium. Invarious embodiments, the RF circuitry 3006 may include switches,filters, amplifiers, etc. to facilitate the communication with thewireless network. RF circuitry 3006 may include a receive signal path,which may include circuitry to down-convert RF signals received from theFEM circuitry 3008 and provide baseband signals to the basebandcircuitry 3010. RF circuitry 3006 may also include a transmit signalpath, which may include circuitry to up-convert baseband signalsprovided by the baseband circuitry 3010 and provide RF output signals tothe FEM circuitry 3008 for transmission.

In some embodiments, the receive signal path of the RF circuitry 3006may include mixer circuitry 3006 a, amplifier circuitry 3006 b andfilter circuitry 3006 c. In some embodiments, the transmit signal pathof the RF circuitry 3006 may include filter circuitry 3006 c and mixercircuitry 3006 a. RF circuitry 3006 may also include synthesizercircuitry 3006 d for synthesizing a frequency for use by the mixercircuitry 3006 a of the receive signal path and the transmit signalpath. In some embodiments, the mixer circuitry 3006 a of the receivesignal path may be configured to down-convert RF signals received fromthe FEM circuitry 3008 based on the synthesized frequency provided bysynthesizer circuitry 3006 d. The amplifier circuitry 3006 b may beconfigured to amplify the down-converted signals and the filtercircuitry 3006 c may be a low-pass filter (LPF) or band-pass filter(BPF) configured to remove unwanted signals from the down-convertedsignals to generate output baseband signals. Output baseband signals maybe provided to the baseband circuitry 3010 for further processing. Insome embodiments, the output baseband signals may be zero-frequencybaseband signals, although this is not a requirement. In someembodiments, mixer circuitry 3006 a of the receive signal path maycomprise passive mixers, although the scope of the embodiments is notlimited in this respect.

In some embodiments, the mixer circuitry 3006 a of the transmit signalpath may be configured to up-convert input baseband signals based on thesynthesized frequency provided by the synthesizer circuitry 3006 d togenerate RF output signals for the FEM circuitry 3008. The basebandsignals may be provided by the baseband circuitry 3010 and may befiltered by filter circuitry 3006 c.

In some embodiments, the mixer circuitry 3006 a of the receive signalpath and the mixer circuitry 3006 a of the transmit signal path mayinclude two or more mixers and may be arranged for quadraturedownconversion and upconversion, respectively. In some embodiments, themixer circuitry 3006 a of the receive signal path and the mixercircuitry 3006 a of the transmit signal path may include two or moremixers and may be arranged for image rejection (e.g., Hartley imagerejection). In some embodiments, the mixer circuitry 3006 a of thereceive signal path and the mixer circuitry 3006 a of the transmitsignal path may be arranged for direct downconversion and directupconversion, respectively. In some embodiments, the mixer circuitry3006 a of the receive signal path and the mixer circuitry 3006 a of thetransmit signal path may be configured for super-heterodyne operation.

In some embodiments, the output baseband signals and the input basebandsignals may be analog baseband signals, although the scope of theembodiments is not limited in this respect. In some alternateembodiments, the output baseband signals and the input baseband signalsmay be digital baseband signals. In these alternate embodiments, the RFcircuitry 3006 may include analog-to-digital converter (ADC) anddigital-to-analog converter (DAC) circuitry and the baseband circuitry3010 may include a digital baseband interface to communicate with the RFcircuitry 3006.

In some dual-mode embodiments, a separate radio IC circuitry may beprovided for processing signals for each spectrum, although the scope ofthe embodiments is not limited in this respect.

In some embodiments, the synthesizer circuitry 3006 d may be afractional-N synthesizer or a fractional N/N+1 synthesizer, although thescope of the embodiments is not limited in this respect as other typesof frequency synthesizers may be suitable. For example, synthesizercircuitry 3006 d may be a delta-sigma synthesizer, a frequencymultiplier, or a synthesizer comprising a phase-locked loop with afrequency divider.

The synthesizer circuitry 3006 d may be configured to synthesize anoutput frequency for use by the mixer circuitry 3006 a of the RFcircuitry 3006 based on a frequency input and a divider control input.In some embodiments, the synthesizer circuitry 3006 d may be afractional N/N+1 synthesizer.

In some embodiments, frequency input may be provided by a voltagecontrolled oscillator (VCO), although that is not a requirement. Dividercontrol input may be provided by either the baseband circuitry 3010 orthe application circuitry 2805/2905 depending on the desired outputfrequency. In some embodiments, a divider control input (e.g., N) may bedetermined from a look-up table based on a channel indicated by theapplication circuitry 2805/2905.

Synthesizer circuitry 3006 d of the RF circuitry 3006 may include adivider, a delay-locked loop (DLL), a multiplexer and a phaseaccumulator. In some embodiments, the divider may be a dual modulusdivider (DMD) and the phase accumulator may be a digital phaseaccumulator (DPA). In some embodiments, the DMD may be configured todivide the input signal by either N or N+1 (e.g., based on a carry out)to provide a fractional division ratio. In some example embodiments, theDLL may include a set of cascaded, tunable, delay elements, a phasedetector, a charge pump and a D-type flip-flop. In these embodiments,the delay elements may be configured to break a VCO period up into Ndequal packets of phase, where Nd is the number of delay elements in thedelay line. In this way, the DLL provides negative feedback to helpensure that the total delay through the delay line is one VCO cycle.

In some embodiments, synthesizer circuitry 3006 d may be configured togenerate a carrier frequency as the output frequency, while in otherembodiments, the output frequency may be a multiple of the carrierfrequency (e.g., twice the carrier frequency, four times the carrierfrequency) and used in conjunction with quadrature generator and dividercircuitry to generate multiple signals at the carrier frequency withmultiple different phases with respect to each other. In someembodiments, the output frequency may be a LO frequency (fLO). In someembodiments, the RF circuitry 3006 may include an IQ/polar converter.

FEM circuitry 3008 may include a receive signal path, which may includecircuitry configured to operate on RF signals received from antennaarray 3011, amplify the received signals and provide the amplifiedversions of the received signals to the RF circuitry 3006 for furtherprocessing. FEM circuitry 3008 may also include a transmit signal path,which may include circuitry configured to amplify signals fortransmission provided by the RF circuitry 3006 for transmission by oneor more of antenna elements of antenna array 3011. In variousembodiments, the amplification through the transmit or receive signalpaths may be done solely in the RF circuitry 3006, solely in the FEMcircuitry 3008, or in both the RF circuitry 3006 and the FEM circuitry3008.

In some embodiments, the FEM circuitry 3008 may include a TX/RX switchto switch between transmit mode and receive mode operation. The FEMcircuitry 3008 may include a receive signal path and a transmit signalpath. The receive signal path of the FEM circuitry 3008 may include anLNA to amplify received RF signals and provide the amplified received RFsignals as an output (e.g., to the RF circuitry 3006). The transmitsignal path of the FEM circuitry 3008 may include a power amplifier (PA)to amplify input RF signals (e.g., provided by RF circuitry 3006), andone or more filters to generate RF signals for subsequent transmissionby one or more antenna elements of the antenna array 3011.

The antenna array 3011 comprises one or more antenna elements, each ofwhich is configured convert electrical signals into radio waves totravel through the air and to convert received radio waves intoelectrical signals. For example, digital baseband signals provided bythe baseband circuitry 3010 is converted into analog RF signals (e.g.,modulated waveform) that will be amplified and transmitted via theantenna elements of the antenna array 3011 including one or more antennaelements (not shown). The antenna elements may be omnidirectional,direction, or a combination thereof. The antenna elements may be formedin a multitude of arranges as are known and/or discussed herein. Theantenna array 3011 may comprise microstrip antennas or printed antennasthat are fabricated on the surface of one or more printed circuitboards. The antenna array 3011 may be formed in as a patch of metal foil(e.g., a patch antenna) in a variety of shapes, and may be coupled withthe RF circuitry 3006 and/or FEM circuitry 3008 using metal transmissionlines or the like.

Processors of the application circuitry 2805/2905 and processors of thebaseband circuitry 3010 may be used to execute elements of one or moreinstances of a protocol stack. For example, processors of the basebandcircuitry 3010, alone or in combination, may be used execute Layer 3,Layer 2, or Layer 1 functionality, while processors of the applicationcircuitry 2805/2905 may utilize data (e.g., packet data) received fromthese layers and further execute Layer 4 functionality (e.g., TCP andUDP layers). As referred to herein, Layer 3 may comprise a RRC layer,described in further detail below. As referred to herein, Layer 2 maycomprise a MAC layer, an RLC layer, and a PDCP layer, described infurther detail below. As referred to herein, Layer 1 may comprise a PHYlayer of a UE/RAN node, described in further detail below.

FIG. 31 illustrates various protocol functions that may be implementedin a wireless communication device according to various embodiments. Inparticular, FIG. 31 includes an arrangement 3100 showinginterconnections between various protocol layers/entities. The followingdescription of FIG. 31 is provided for various protocol layers/entitiesthat operate in conjunction with the 5G/NR system standards and LTEsystem standards, but some or all of the aspects of FIG. 31 may beapplicable to other wireless communication network systems as well.

The protocol layers of arrangement 3100 may include one or more of PHY3110, MAC 3120, RLC 3130, PDCP 3140, SDAP 3147, RRC 3155, and NAS layer3157, in addition to other higher layer functions not illustrated. Theprotocol layers may include one or more service access points (e.g.,items 3159, 3156, 3150, 3149, 3145, 3135, 3125, and 3115 in FIG. 31 )that may provide communication between two or more protocol layers.

The PHY 3110 may transmit and receive physical layer signals 3105 thatmay be received from or transmitted to one or more other communicationdevices. The physical layer signals 3105 may comprise one or morephysical channels, such as those discussed herein. The PHY 3110 mayfurther perform link adaptation or adaptive modulation and coding (AMC),power control, cell search (e.g., for initial synchronization andhandover purposes), and other measurements used by higher layers, suchas the RRC 3155. The PHY 3110 may still further perform error detectionon the transport channels, forward error correction (FEC)coding/decoding of the transport channels, modulation/demodulation ofphysical channels, interleaving, rate matching, mapping onto physicalchannels, and MIMO antenna processing. In embodiments, an instance ofPHY 3110 may process requests from and provide indications to aninstance of MAC 3120 via one or more PHY-SAP 3115. According to someembodiments, requests and indications communicated via PHY-SAP 3115 maycomprise one or more transport channels.

Instance(s) of MAC 3120 may process requests from, and provideindications to, an instance of RLC 3130 via one or more MAC-SAPs 3125.These requests and indications communicated via the MAC-SAP 3125 maycomprise one or more logical channels. The MAC 3120 may perform mappingbetween the logical channels and transport channels, multiplexing of MACSDUs from one or more logical channels onto TBs to be delivered to PHY3110 via the transport channels, de-multiplexing MAC SDUs to one or morelogical channels from TBs delivered from the PHY 3110 via transportchannels, multiplexing MAC SDUs onto TBs, scheduling informationreporting, error correction through HARQ, and logical channelprioritization.

Instance(s) of RLC 3130 may process requests from and provideindications to an instance of PDCP 3140 via one or more radio linkcontrol service access points (RLC-SAP) 3135. These requests andindications communicated via RLC-SAP 3135 may comprise one or more RLCchannels. The RLC 3130 may operate in a plurality of modes of operation,including: Transparent Mode™, Unacknowledged Mode (UM), and AcknowledgedMode (AM). The RLC 3130 may execute transfer of upper layer protocoldata units (PDUs), error correction through automatic repeat request(ARQ) for AM data transfers, and concatenation, segmentation andreassembly of RLC SDUs for UM and AM data transfers. The RLC 3130 mayalso execute re-segmentation of RLC data PDUs for AM data transfers,reorder RLC data PDUs for UM and AM data transfers, detect duplicatedata for UM and AM data transfers, discard RLC SDUs for UM and AM datatransfers, detect protocol errors for AM data transfers, and perform RLCre-establishment.

Instance(s) of PDCP 3140 may process requests from and provideindications to instance(s) of RRC 3155 and/or instance(s) of SDAP 3147via one or more packet data convergence protocol service access points(PDCP-SAP) 3145. These requests and indications communicated viaPDCP-SAP 3145 may comprise one or more radio bearers. The PDCP 3140 mayexecute header compression and decompression of IP data, maintain PDCPSequence Numbers (SNs), perform in-sequence delivery of upper layer PDUsat re-establishment of lower layers, eliminate duplicates of lower layerSDUs at re-establishment of lower layers for radio bearers mapped on RLCAM, cipher and decipher control plane data, perform integrity protectionand integrity verification of control plane data, control timer-baseddiscard of data, and perform security operations (e.g., ciphering,deciphering, integrity protection, integrity verification, etc.).

Instance(s) of SDAP 3147 may process requests from and provideindications to one or more higher layer protocol entities via one ormore SDAP-SAP 3149. These requests and indications communicated viaSDAP-SAP 3149 may comprise one or more QoS flows. The SDAP 3147 may mapQoS flows to DRBs, and vice versa, and may also mark QFIs in DL and ULpackets. A single SDAP entity 3147 may be configured for an individualPDU session. In the UL direction, the NG-RAN XQ10 may control themapping of QoS Flows to DRB(s) in two different ways, reflective mappingor explicit mapping. For reflective mapping, the SDAP 3147 of a UE XQ01may monitor the QFIs of the DL packets for each DRB, and may apply thesame mapping for packets flowing in the UL direction. For a DRB, theSDAP 3147 of the UE XQ01 may map the UL packets belonging to the QoSflows(s) corresponding to the QoS flow ID(s) and PDU session observed inthe DL packets for that DRB. To enable reflective mapping, the NG-RAN2710 may mark DL packets over the Uu interface with a QoS flow ID. Theexplicit mapping may involve the RRC 3155 configuring the SDAP 3147 withan explicit QoS flow to DRB mapping rule, which may be stored andfollowed by the SDAP 3147. In embodiments, the SDAP 3147 may only beused in NR implementations and may not be used in LTE implementations.

The RRC 3155 may configure, via one or more management service accesspoints (M-SAP), aspects of one or more protocol layers, which mayinclude one or more instances of PHY 3110, MAC 3120, RLC 3130, PDCP 3140and SDAP 3147. In embodiments, an instance of RRC 3155 may processrequests from and provide indications to one or more NAS entities 3157via one or more RRC-SAPs 3156. The main services and functions of theRRC 3155 may include broadcast of system information (e.g., included inMIBs or SIBs related to the NAS), broadcast of system informationrelated to the access stratum (AS), paging, establishment, maintenanceand release of an RRC connection between the UE XQ01 and RAN XQ10 (e.g.,RRC connection paging, RRC connection establishment, RRC connectionmodification, and RRC connection release), establishment, configuration,maintenance and release of point to point Radio Bearers, securityfunctions including key management, inter-RAT mobility, and measurementconfiguration for UE measurement reporting. The MIBs and SIBs maycomprise one or more IEs, which may each comprise individual data fieldsor data structures.

The NAS 3157 may form the highest stratum of the control plane betweenthe UE XQ01 and the AMF 2721. The NAS 3157 may support the mobility ofthe UEs XQ01 and the session management procedures to establish andmaintain IP connectivity between the UE XQ01 and a P-GW in LTE systems.

According to various embodiments, one or more protocol entities ofarrangement 3100 may be implemented in UEs XQ01, RAN nodes XQ11, AMF2721 in NR implementations or MME 2621 in LTE implementations, UPF 2702in NR implementations or S-GW 2622 and P-GW 2623 in LTE implementations,or the like to be used for control plane or user plane communicationsprotocol stack between the aforementioned devices. In such embodiments,one or more protocol entities that may be implemented in one or more ofUE XQ01, gNB XQ11, AMF 2721, etc. may communicate with a respective peerprotocol entity that may be implemented in or on another device usingthe services of respective lower layer protocol entities to perform suchcommunication. In some embodiments, a gNB-CU of the gNB XQ11 may hostthe RRC 3155, SDAP 3147, and PDCP 3140 of the gNB that controls theoperation of one or more gNB-DUs, and the gNB-DUs of the gNB XQ11 mayeach host the RLC 3130, MAC 3120, and PHY 3110 of the gNB XQ11.

In a first example, a control plane protocol stack may comprise, inorder from highest layer to lowest layer, NAS 3157, RRC 3155, PDCP 3140,RLC 3130, MAC 3120, and PHY 3110. In this example, upper layers 3160 maybe built on top of the NAS 3157, which includes an IP layer 3161, anSCTP 3162, and an application layer signaling protocol (AP) 3163.

In NR implementations, the AP 3163 may be an NG application protocollayer (NGAP or NG-AP) 3163 for the NG interface XQ13 defined between theNG-RAN node XQ11 and the AMF 2721, or the AP 3163 may be an Xnapplication protocol layer (XnAP or Xn-AP) 3163 for the Xn interfaceXQ12 that is defined between two or more RAN nodes XQ11.

The NG-AP 3163 may support the functions of the NG interface XQ13 andmay comprise Elementary Procedures (EPs). An NG-AP EP may be a unit ofinteraction between the NG-RAN node XQ11 and the AMF 2721. The NG-AP3163 services may comprise two groups: UE-associated services (e.g.,services related to a UE XQ01) and non-UE-associated services (e.g.,services related to the whole NG interface instance between the NG-RANnode XQ11 and AMF 2721). These services may include functions including,but not limited to: a paging function for the sending of paging requeststo NG-RAN nodes XQ11 involved in a particular paging area; a UE contextmanagement function for allowing the AMF 2721 to establish, modify,and/or release a UE context in the AMF 2721 and the NG-RAN node XQ11; amobility function for UEs XQ01 in ECM-CONNECTED mode for intra-systemHOs to support mobility within NG-RAN and inter-system HOs to supportmobility from/to EPS systems; a NAS Signaling Transport function fortransporting or rerouting NAS messages between UE XQ01 and AMF 2721; aNAS node selection function for determining an association between theAMF 2721 and the UE XQ01; NG interface management function(s) forsetting up the NG interface and monitoring for errors over the NGinterface; a warning message transmission function for providing meansto transfer warning messages via NG interface or cancel ongoingbroadcast of warning messages; a Configuration Transfer function forrequesting and transferring of RAN configuration information (e.g., SONinformation, performance measurement (PM) data, etc.) between two RANnodes XQ11 via CN XQ20; and/or other like functions.

The XnAP 3163 may support the functions of the Xn interface XQ12 and maycomprise XnAP basic mobility procedures and XnAP global procedures. TheXnAP basic mobility procedures may comprise procedures used to handle UEmobility within the NG RAN XQ11 (or E-UTRAN 2610), such as handoverpreparation and cancellation procedures, SN Status Transfer procedures,UE context retrieval and UE context release procedures, RAN pagingprocedures, dual connectivity related procedures, and the like. The XnAPglobal procedures may comprise procedures that are not related to aspecific UE XQ01, such as Xn interface setup and reset procedures,NG-RAN update procedures, cell activation procedures, and the like.

In LTE implementations, the AP 3163 may be an S1 Application Protocollayer (S1-AP) 3163 for the S1 interface XQ13 defined between an E-UTRANnode XQ11 and an MME, or the AP 3163 may be an X2 application protocollayer (X2AP or X2-AP) 3163 for the X2 interface XQ12 that is definedbetween two or more E-UTRAN nodes XQ11.

The S1 Application Protocol layer (S1-AP) 3163 may support the functionsof the S1 interface, and similar to the NG-AP discussed previously, theS1-AP may comprise S1-AP EPs. An S1-AP EP may be a unit of interactionbetween the E-UTRAN node XQ11 and an MME 2621 within an LTE CN XQ20. TheS1-AP 3163 services may comprise two groups: UE-associated services andnon UE-associated services. These services perform functions including,but not limited to: E-UTRAN Radio Access Bearer (E-RAB) management, UEcapability indication, mobility, NAS signaling transport, RANInformation Management (RIM), and configuration transfer.

The X2AP 3163 may support the functions of the X2 interface XQ12 and maycomprise X2AP basic mobility procedures and X2AP global procedures. TheX2AP basic mobility procedures may comprise procedures used to handle UEmobility within the E-UTRAN XQ20, such as handover preparation andcancellation procedures, SN Status Transfer procedures, UE contextretrieval and UE context release procedures, RAN paging procedures, dualconnectivity related procedures, and the like. The X2AP globalprocedures may comprise procedures that are not related to a specific UEXQ01, such as X2 interface setup and reset procedures, load indicationprocedures, error indication procedures, cell activation procedures, andthe like.

The SCTP layer (alternatively referred to as the SCTP/IP layer) 3162 mayprovide guaranteed delivery of application layer messages (e.g., NGAP orXnAP messages in NR implementations, or S1-AP or X2AP messages in LTEimplementations). The SCTP 3162 may ensure reliable delivery ofsignaling messages between the RAN node XQ11 and the AMF 2721/MME 2621based, in part, on the IP protocol, supported by the IP 3161. TheInternet Protocol layer (IP) 3161 may be used to perform packetaddressing and routing functionality. In some implementations the IPlayer 3161 may use point-to-point transmission to deliver and conveyPDUs. In this regard, the RAN node XQ11 may comprise L2 and L1 layercommunication links (e.g., wired or wireless) with the MME/AMF toexchange information.

In a second example, a user plane protocol stack may comprise, in orderfrom highest layer to lowest layer, SDAP 3147, PDCP 3140, RLC 3130, MAC3120, and PHY 3110. The user plane protocol stack may be used forcommunication between the UE XQ01, the RAN node XQ11, and UPF 2702 in NRimplementations or an S-GW 2622 and P-GW 2623 in LTE implementations. Inthis example, upper layers 3151 may be built on top of the SDAP 3147,and may include a user datagram protocol (UDP) and IP security layer(UDP/IP) 3152, a General Packet Radio Service (GPRS) Tunneling Protocolfor the user plane layer (GTP-U) 3153, and a User Plane PDU layer (UPPDU) 3163.

The transport network layer 3154 (also referred to as a “transportlayer”) may be built on IP transport, and the GTP-U 3153 may be used ontop of the UDP/IP layer 3152 (comprising a UDP layer and IP layer) tocarry user plane PDUs (UP-PDUs). The IP layer (also referred to as the“Internet layer”) may be used to perform packet addressing and routingfunctionality. The IP layer may assign IP addresses to user data packetsin any of IPv4, IPv6, or PPP formats, for example.

The GTP-U 3153 may be used for carrying user data within the GPRS corenetwork and between the radio access network and the core network. Theuser data transported can be packets in any of IPv4, IPv6, or PPPformats, for example. The UDP/IP 3152 may provide checksums for dataintegrity, port numbers for addressing different functions at the sourceand destination, and encryption and authentication on the selected dataflows. The RAN node XQ11 and the S-GW 2622 may utilize an S1-U interfaceto exchange user plane data via a protocol stack comprising an L1 layer(e.g., PHY 3110), an L2 layer (e.g., MAC 3120, RLC 3130, PDCP 3140,and/or SDAP 3147), the UDP/IP layer 3152, and the GTP-U 3153. The S-GW2622 and the P-GW 2623 may utilize an S5/S8a interface to exchange userplane data via a protocol stack comprising an L1 layer, an L2 layer, theUDP/IP layer 3152, and the GTP-U 3153. As discussed previously, NASprotocols may support the mobility of the UE XQ01 and the sessionmanagement procedures to establish and maintain IP connectivity betweenthe UE XQ01 and the P-GW 2623.

Moreover, although not shown by FIG. 31 , an application layer may bepresent above the AP 3163 and/or the transport network layer 3154. Theapplication layer may be a layer in which a user of the UE XQ01, RANnode XQ11, or other network element interacts with software applicationsbeing executed, for example, by application circuitry 2805 orapplication circuitry 2905, respectively. The application layer may alsoprovide one or more interfaces for software applications to interactwith communications systems of the UE XQ01 or RAN node XQ11, such as thebaseband circuitry 3010. In some implementations the IP layer and/or theapplication layer may provide the same or similar functionality aslayers 5-7, or portions thereof, of the Open Systems Interconnection(OSI) model (e.g., OSI Layer 7—the application layer, OSI Layer 6—thepresentation layer, and OSI Layer 5—the session layer).

FIG. 32 is a block diagram illustrating components, according to someexample embodiments, able to read instructions from a machine-readableor computer-readable medium (e.g., a non-transitory machine-readablestorage medium) and perform any one or more of the methodologiesdiscussed herein. Specifically, FIG. 32 shows a diagrammaticrepresentation of hardware resources 3200 including one or moreprocessors (or processor cores) 3210, one or more memory/storage devices3220, and one or more communication resources 3230, each of which may becommunicatively coupled via a bus 3240. For embodiments where nodevirtualization (e.g., NFV) is utilized, a hypervisor 3202 may beexecuted to provide an execution environment for one or more networkslices/sub-slices to utilize the hardware resources 3200.

The processors 3210 may include, for example, a processor 3212 and aprocessor 3214. The processor(s) 3210 may be, for example, a centralprocessing unit (CPU), a reduced instruction set computing (RISC)processor, a complex instruction set computing (CISC) processor, agraphics processing unit (GPU), a DSP such as a baseband processor, anASIC, an FPGA, a radio-frequency integrated circuit (RFIC), anotherprocessor (including those discussed herein), or any suitablecombination thereof.

The memory/storage devices 3220 may include main memory, disk storage,or any suitable combination thereof. The memory/storage devices 3220 mayinclude, but are not limited to, any type of volatile or nonvolatilememory such as dynamic random access memory (DRAM), static random accessmemory (SRAM), erasable programmable read-only memory (EPROM),electrically erasable programmable read-only memory (EEPROM), Flashmemory, solid-state storage, etc.

The communication resources 3230 may include interconnection or networkinterface components or other suitable devices to communicate with oneor more peripheral devices 3204 or one or more databases 3206 via anetwork 3208. For example, the communication resources 3230 may includewired communication components (e.g., for coupling via USB), cellularcommunication components, NFC components, Bluetooth® (or Bluetooth® LowEnergy) components, Wi-Fi® components, and other communicationcomponents.

Instructions 3250 may comprise software, a program, an application, anapplet, an app, or other executable code for causing at least any of theprocessors 3210 to perform any one or more of the methodologiesdiscussed herein. The instructions 3250 may reside, completely orpartially, within at least one of the processors 3210 (e.g., within theprocessor's cache memory), the memory/storage devices 3220, or anysuitable combination thereof. Furthermore, any portion of theinstructions 3250 may be transferred to the hardware resources 3200 fromany combination of the peripheral devices 3204 or the databases 3206.Accordingly, the memory of processors 3210, the memory/storage devices3220, the peripheral devices 3204, and the databases 3206 are examplesof computer-readable and machine-readable media.

Example Procedures

In some embodiments, the electronic device(s), network(s), system(s),chip(s) or component(s), or portions or implementations thereof, ofFIGS. 25-32 , or some other figure herein, may be configured to performone or more processes, techniques, or methods as described herein, orportions thereof. One such process is depicted in FIG. 22 . For example,the process may include, at 2201, receiving route information formultiple routes between a UE and a core network via the IAB node. At2202, the process may include receiving configuration information toindicate a split of a data stream of the UE between the multiple routes,wherein the configuration information indicates respective fractions ofthe data stream that are to be sent on respective routes.

At 2203, the process may include receiving data packets of the datastream. At 2204, the process may include selecting one of the multipleroutes for respective data packets based on the configurationinformation. For example, the routes may be selected such that averagefractions of data transmitted via the respective routes substantiallymatch the configured fractions. In some embodiments, the averagefractions may be determined over a predetermined time period or numberof data packets. Additionally, or alternatively, the average fractionssubstantially match the configured fractions if they are within athreshold of the configured fractions or within a rounding error of theconfigured fractions (e.g., as close as possible to the configuredfractions given the number of data packets used to determine the averagefractions).

In various embodiments, the process of FIG. 22 may be performed by anIAB node or a portion thereof. For example, in some embodiments, some orall aspects of the process of FIG. 22 may be performed by basebandcircuitry of the IAB node.

FIG. 23 illustrates another process in accordance with variousembodiments. At 2301, the process may include receiving configurationinformation to indicate, for a data stream associated with a routingidentifier, fractions of the data stream that are to be sent over two ormore respective radio links. In some embodiments, the radio links may beegress radio links.

At 2302, the process may include receiving a data packet associated withthe routing identifier. At 2303, the process may include selecting afirst radio link of the two or more radio links based on theconfiguration information. At 2304, the process may include transmittingor causing to transmit the data packet on the selected first radio link.

For example, the first radio link may be selected such that averagefractions of data transmitted via the respective radio linkssubstantially match the configured fractions. In some embodiments, theaverage fractions may be determined over a predetermined time period ornumber of data packets. Additionally, or alternatively, the averagefractions substantially match the configured fractions if they arewithin a threshold of the configured fractions or within a roundingerror of the configured fractions (e.g., as close as possible to theconfigured fractions given the number of data packets used to determinethe average fractions).

In various embodiments, the process of FIG. 23 may be performed by anIAB node or a portion thereof. For example, in some embodiments, some orall aspects of the process of FIG. 23 may be performed by basebandcircuitry of the IAB node.

FIG. 24 illustrates another process in accordance with variousembodiments. The process of FIG. 24 may be performed by an IAB node orcomponents thereof, for example, circuitry that implements a BAP layerin the IAB node.

The process may include, at 2401, receiving a first sequence of packetsegments.

The process may further include, at 2402, determining a linkreliability. In some embodiments, the determination of the linkreliability may be performed by decoding the first sequence of packetsegments and determining how many encoded segments have been sent on aparticular link.

If it is determined that the link reliability is less than a target (forexample, the number of encoded segments is less than a predefinednumber), the process may further include, at 2403, increasing a numberof transmitted encoded segments. This may be done by re-encoding thepacket and providing one or more re-encoded packet segments into atransmission buffer for transmission on the link. In some embodiments,the re-encoded packet segments may be added to original encoded packetsthat are in the transmission buffer or have already been transmittedsuch that a total number of packet segments to be transmitted is equalto the predefined number.

If it is determined that the link reliability is greater than a target(for example, the number of encoded segments is greater than thepredefined number), the process may further include, at 2404, decreasinga number of transmitted encoded segments. In some embodiments, one ormore encoded segments received may be not transmitted to avoidunnecessary redundancy.

For one or more embodiments, at least one of the components set forth inone or more of the preceding figures may be configured to perform one ormore operations, techniques, processes, and/or methods as set forth inthe example section below. For example, the baseband circuitry asdescribed above in connection with one or more of the preceding figuresmay be configured to operate in accordance with one or more of theexamples set forth below. For another example, circuitry associated witha UE, base station, network element, etc. as described above inconnection with one or more of the preceding figures may be configuredto operate in accordance with one or more of the examples set forthbelow in the example section.

EXAMPLES

Example 1 may include a method in a source node of transmitting data toa destination node in a multi-hop wireless network, comprising:receiving a packet to be transmitted to the destination node;determining a set of weights corresponding to each of a set of routes tothe destination node; generating network coded segments based on thereceived packet; and transmitting network coded segments on each routeof the set of routes, wherein the number of network coded segments isproportional to the weight corresponding to the route.

Example 2 may include the method of Example 1 or some other exampleherein, wherein the set of weights are determined based on informationprovided by the destination node, which includes ratios of number ofsegments received by the destination node via each route of the set ofroutes.

Example 3 may include the method of Example 1 or some other exampleherein, wherein generating network coded segments is performed at PDCPlayer.

Example 4 may include the method of Example 1 or some other exampleherein, wherein determining the set of weights is based ondata-transmission capabilities of each of the set of routes.

Example 5 may include the method of Example 1 or some other exampleherein, wherein the set of weights are to cause a probability oftransmitting a network coded segment over a route to be proportional toa supported data rate of the route.

Example 6 may include a method for transmitting data over multipleroutes in a relay node servicing a UE, comprising: configuring multipleroutes from the relay node to a destination node, wherein each of themultiple routes has a distinct routing identifier; receiving informationfor configuring a split of the data stream of the UE, wherein theinformation comprises fractions of the UE's data that is to beassociated with the distinct routing identifiers; selecting, for a givenpacket, one of the distinct routing identifiers according to thefraction corresponding to chosen routing identifier; and transmitting apacket with a header, wherein the header includes the chosen routingidentifier.

Example 7 may include the method of example 6 or some other exampleherein, wherein selecting one of the distinct routing identifierscomprises: selecting the routing identifier such that the long termaveraged fractions of data transmitted via the routes corresponding tothe distinct routing identifiers substantially matches the configuredfractions.

Example 8 may include a method of transmitting data over multiple routesin a relay node comprising: receiving information for configuring asplit of a data stream corresponding to a first routing identifier,wherein the information comprises fractions of the data stream that areto be associated with each of two or more egress radio links; receivinga packet associated with the first routing identifier; determining thatthere are two or more egress radio links corresponding to the firstrouting identifier; selecting one of the two or more egress radio linksaccording to the fraction corresponding to the selected radio link; andtransmitting the packet on the selected egress radio link.

Example 9 may include the method of example 8 or some other exampleherein, wherein selecting one of the egress radio links comprises:selecting the egress link such that the long term averaged fractions ofdata transmitted via the two or more egress links substantially matchesthe configured fractions.

Example 10 may include a method of an IAB node, the method comprising:receiving route information for multiple routes between a UE and a corenetwork via the IAB node; receiving configuration information toindicate a split of a data stream of the UE between the multiple routes,wherein the configuration information indicates respective fractions ofthe data stream that are to be sent on respective routes; receiving datapackets of the data stream; and selecting one of the multiple routes forrespective data packets based on the configuration information.

Example 11 may include the method of example 10 or some other exampleherein, wherein the route information includes respective routeidentifiers for individual routes of the multiple routes.

Example 12 may include the method of example 11 or some other exampleherein, wherein the configuration information indicates the fractionsassociated with respective route identifiers.

Example 13 may include the method of example 11-12 or some other exampleherein, further comprising transmitting or causing transmission of thedata packets with the selected route identifier included in therespective data packet.

Example 14 may include the method of example 13 or some other exampleherein, wherein the selected route identifier is included in a header ofthe respective data packet.

Example 15 may include the method of example 10-14 or some other exampleherein, wherein selecting one of the multiple routes for the respectivedata packets includes selecting one of the multiple routes such thataverage fractions of data transmitted via the respective routessubstantially match the configured fractions.

Example 16 may include the method of example 15 or some other exampleherein, wherein the average fractions are over a predetermined timeperiod or number of data packets.

Example 17 may include the method of example 15-16 or some other exampleherein, wherein the average fractions substantially match the configuredfractions if they are within a threshold of the configured fractions orwithin a rounding error of the configured fractions.

Example 18 may include a method of an IAB node, the method comprising:receiving configuration information to indicate, for a data streamassociated with a routing identifier, fractions of the data stream thatare to be sent over two or more respective radio links; receiving a datapacket associated with the routing identifier; selecting a first radiolink of the two or more radio links based on the configurationinformation; and transmitting or causing to transmit the data packet onthe selected radio link.

Example 19 may include the method of example 18 or some other exampleherein, wherein the radio links are egress radio links.

Example 20 may include the method of example 18-19 or some other exampleherein, wherein selecting the first radio link based on theconfiguration information comprises selecting the first radio link suchthat average fractions of data associated with the routing identifierthat are transmitted via the respective radio links substantiallymatches the configured fractions.

Example 21 may include the method of example 20 or some other exampleherein, wherein the average fractions are over a predetermined timeperiod or number of data packets.

Example 22 may include the method of example 20-21 or some other exampleherein, wherein the average fractions substantially match the configuredfractions if they are within a threshold of the configured fractions orwithin a rounding error of the configured fractions.

Example 23 may include a method in an IAB node of performing initialsetup comprising: establishing a connection to the network via a parentnode; broadcasting information to enable incoming access requests,wherein the broadcast information further indicates that UEs are barredfrom performing access requests to the iab node; receiving an indicationfrom the network that the initial setup phase is complete; and modifyingthe broadcast system information to indicate that UEs are no longerbarred from performing access requests to the iab node.

Example 24 may include a method in a first IAB node of performinginitial setup, comprising: identifying a second IAB node with which toattach; receiving broadcast system information from the second IAB node,wherein the broadcast system information is to indicate that accessrequests by UEs are barred; transmitting an access request to the secondIAB node, wherein the first IAB node indicates during the accessprocedure that it is an IAB node; and establishing a connection to thenetwork through the second IAB node.

Example 25 may include the method for integration of relay nodes into anetwork comprising: signaling a threshold from a first set of nodes thatare integrated into the network; receiving an access request from asecond node that is not in the first set of nodes, at a node in thefirst set of nodes; integrating the second node into the network; andsignaling a threshold from a second set of nodes, wherein the second setof nodes includes the first set of nodes and the second node.

Example 26 may include a method in a relay node of integrating into thenetwork comprising: receiving threshold information from a first set ofnodes that are integrated into the network; performing measurements ofsignals of the first set of nodes to determine which of the first set ofnodes' measurements are above their corresponding thresholds;determining a second set of nodes, wherein the second set of nodes is asubset of the first set of nodes for which the measurements are abovethe corresponding thresholds; and selecting as a parent a second node inthe second set of nodes such that the measurement of the second node isthe better than the measurement of the other nodes in the second set.

Example 27 may include the method of 26 further comprising: determiningthat no nodes in the first set of nodes have measurements that are abovetheir corresponding threshold; receiving an indication of new thresholdinformation; determining a second set of nodes, wherein the second setof nodes is a subset of the first set of nodes for which themeasurements are above the corresponding thresholds, based on the newthreshold information; and selecting as a parent a second node in thesecond set of nodes such that the measurement of the second node is thebetter than the measurement of the other nodes in the second set.

Example 28 may include a method of transmitting data in an IAB node, themethod comprising: receiving a first sequence of packet segments fromone or more ingress links; decoding, if the first sequence of packetsegments includes a minimum number of segments have been received, apacket; and transmitting, on one or more egress links, a second sequenceof packet segments generated from the packet.

Example 29 may include the method of example 28 or some other exampleherein, further comprising: forwarding one or more segments of the firstsequence of packet segments on the one or more egress links prior toreceiving the minimum number of segments.

Example 30 may include the method of example 29 or some other exampleherein, wherein the number of segments of the first sequence of packetsegments forwarded is fewer than the number of received first sequenceof packet segments.

Example 31 may include the method of example 29 or some other exampleherein, wherein the number of segments of the first sequence of packetsegments forwarded on an egress link depends on the link quality of theegress link.

Example 32 may include the method of example 28 or some other exampleherein, wherein the number of segments in the second sequence of packetsegments transmitted over an egress link depends on the link quality ofthe egress link.

Example 33 may include a method of adaptive coded forwarding comprising:

-   -   determining a reliability target on a link is less than a        predetermined threshold; and encoding and forwarding extra        outgoing segments based on said determining.

Example 34 may include the method of example 33 or some other exampleherein, wherein determining the reliability target on the linkcomprises: determining a sufficient number of encoded segments have beenreceived at a node; decoding a packet based on said determining thesufficient number has been received; and determining a number of encodedsegments sent on one or more outgoing links is less than a predefinednumber.

Example 35 may include the method of example 34 or some other exampleherein, wherein encoding and forwarding extra outgoing symbols based onsaid determining comprises: encoding the packet into additional segmentsfor transmission on the link as the extra outgoing symbols, wherein theadditional segments and the number of encoded segments is at least thepredefined number.

Example 36 may include a method of adaptive coded forwarding comprising:receiving encoded packet segments of a link; forwarding the encodedpacket segments to a pre-transmission buffer associated with the link;determining a number of the encoded packet segments in thepre-transmission buffer is sufficient to decode a packet; decoding thepacket based on the number of the encoded packet segments; re-encodingthe packet to generate re-encoded packet segments; supply thepre-transmission buffer with the re-encoded packet segments; determininga number of transmitted segments is less than a predefined number;adding one or more re-encoded packet segments to a transmission bufferto provide a total number of segments to be transmitted to be apredefined number.

Example 37 may include the method of example 36 or some other exampleherein, further comprising: transmitting segments in the transmissionbuffer.

Example 38 may include the method of example 37 or some other exampleherein, further comprising: emptying the pre-transmission buffer.

Example 39 may include the method of example 36 or some other exampleherein, wherein the decoding and encoding is performed by a backhauladaptation (BAP) layer of an integrated access and backhaul (IAB) node.

Example 40 may include a method of adaptive coded forwarding comprising:

-   -   determining a reliability target on a link is greater than a        predetermined threshold; and throttling a number of outgoing        symbols to reduce excess redundancy based on said determining.

Example 41 may include a method comprising: receiving encoded segmentson a link; determining a link reliability is greater than apredetermined threshold or less than a predetermined threshold; ifgreater than the predetermined threshold, reducing a number of encodedsegments to be transmitted on the link; and if less than thepredetermined threshold, increasing a number of encoded segments to betransmitted on the link.

Example 42 may include the method of example 41 or some other exampleherein, wherein if greater than the predetermined threshold, reducingthe number of encoded segments to be transmitted on the link by a numbersufficient to set the link reliability to the predetermined threshold.

Example 43 may include the method of example 41 or some other exampleherein, wherein if less than the predetermined threshold, increasing thenumber of encoded segments to be transmitted on the link by a numbersufficient to set the link reliability to the predetermined threshold.

Example 44 may include the method of example 41 or some other exampleherein, wherein increasing the number of encoded segments comprises:decoding the encoded segments to obtain packet data; and re-encoding thepacket data into re-encoded segments; and transmitting one or more ofthe re-encoded segments.

Example 45 may include the method of example 44 or some other exampleherein, further comprising transmitting one or more of the re-encodedsegments along with one or more received encoded segments.

Example 46 may include an apparatus comprising means to perform one ormore elements of a method described in or related to any of examples1-45, or any other method or process described herein.

Example 47 may include one or more non-transitory computer-readablemedia comprising instructions to cause an electronic device, uponexecution of the instructions by one or more processors of theelectronic device, to perform one or more elements of a method describedin or related to any of examples 1-45, or any other method or processdescribed herein.

Example 48 may include an apparatus comprising logic, modules, orcircuitry to perform one or more elements of a method described in orrelated to any of examples 1-45, or any other method or processdescribed herein.

Example 49 may include a method, technique, or process as described inor related to any of examples 1-45, or portions or parts thereof.

Example 50 may include an apparatus comprising: one or more processorsand one or more computer-readable media comprising instructions that,when executed by the one or more processors, cause the one or moreprocessors to perform the method, techniques, or process as described inor related to any of examples 1-45, or portions thereof.

Example 51 may include a signal as described in or related to any ofexamples 1-45, or portions or parts thereof.

Example 52 may include a datagram, packet, frame, segment, protocol dataunit (PDU), or message as described in or related to any of examples1-45, or portions or parts thereof, or otherwise described in thepresent disclosure.

Example 53 may include a signal encoded with data as described in orrelated to any of examples 1-45, or portions or parts thereof, orotherwise described in the present disclosure.

Example 54 may include a signal encoded with a datagram, packet, frame,segment, protocol data unit (PDU), or message as described in or relatedto any of examples 1-45, or portions or parts thereof, or otherwisedescribed in the present disclosure.

Example 55 may include an electromagnetic signal carryingcomputer-readable instructions, wherein execution of thecomputer-readable instructions by one or more processors is to cause theone or more processors to perform the method, techniques, or process asdescribed in or related to any of examples 1-45, or portions thereof.

Example 56 may include a computer program comprising instructions,wherein execution of the program by a processing element is to cause theprocessing element to carry out the method, techniques, or process asdescribed in or related to any of examples 1-45, or portions thereof.

Example 57 may include a signal in a wireless network as shown anddescribed herein.

Example 58 may include a method of communicating in a wireless networkas shown and described herein.

Example 59 may include a system for providing wireless communication asshown and described herein.

Example 60 may include a device for providing wireless communication asshown and described herein.

Any of the above-described examples may be combined with any otherexample (or combination of examples), unless explicitly statedotherwise. The foregoing description of one or more implementationsprovides illustration and description, but is not intended to beexhaustive or to limit the scope of embodiments to the precise formdisclosed. Modifications and variations are possible in light of theabove teachings or may be acquired from practice of various embodiments.

Abbreviations

For the purposes of the present document, the following abbreviationsmay apply to the examples and embodiments discussed herein.

-   -   3GPP Third Generation Partnership Project    -   4G Fourth Generation    -   5G Fifth Generation    -   5GC 5G Core network    -   ACK Acknowledgement    -   AF Application Function    -   AM Acknowledged Mode    -   AMBR Aggregate Maximum Bit Rate    -   AMF Access and Mobility Management Function    -   AN Access Network    -   ANR Automatic Neighbour Relation    -   AP Application Protocol, Antenna Port, Access Point    -   API Application Programming Interface    -   APN Access Point Name    -   ARP Allocation and Retention Priority    -   ARQ Automatic Repeat Request    -   AS Access Stratum    -   ASN.1 Abstract Syntax Notation One    -   AUSF Authentication Server Function    -   AWGN Additive White Gaussian Noise    -   BAP Backhaul Adaptation Protocol    -   BCH Broadcast Channel    -   BER Bit Error Ratio    -   BFD Beam Failure Detection    -   BLER Block Error Rate    -   BPSK Binary Phase Shift Keying    -   BRAS Broadband Remote Access Server    -   BSS Business Support System    -   BS Base Station    -   BSR Buffer Status Report    -   BW Bandwidth    -   BWP Bandwidth Part    -   C-RNTI Cell Radio Network Temporary Identity    -   CA Carrier Aggregation, Certification Authority    -   CAPEX CAPital EXpenditure    -   CBRA Contention Based Random Access    -   CC Component Carrier, Country Code, Cryptographic Checksum    -   CCA Clear Channel Assessment    -   CCE Control Channel Element    -   CCCH Common Control Channel    -   CE Coverage Enhancement    -   CDM Content Delivery Network    -   CDMA Code-Division Multiple Access    -   CFRA Contention Free Random Access    -   CG Cell Group    -   CI Cell Identity    -   CID Cell-ID (e.g., positioning method)    -   CIM Common Information Model    -   CIR Carrier to Interference Ratio    -   CK Cipher Key    -   CM Connection Management, Conditional Mandatory    -   CMAS Commercial Mobile Alert Service    -   CMD Command    -   CMS Cloud Management System    -   CO Conditional Optional    -   CoMP Coordinated Multi-Point    -   CORESET Control Resource Set    -   COTS Commercial Off-The-Shelf    -   CP Control Plane, Cyclic Prefix, Connection Point    -   CPD Connection Point Descriptor    -   CPE Customer Premise Equipment    -   CPICH Common Pilot Channel    -   CQI Channel Quality Indicator    -   CPU CSI processing unit, Central Processing Unit    -   C/R Command/Response field bit    -   CRAN Cloud Radio Access Network, Cloud RAN    -   CRB Common Resource Block    -   CRC Cyclic Redundancy Check    -   CRI Channel-State Information Resource Indicator, CSI-RS        Resource Indicator    -   C-RNTI Cell RNTI    -   CS Circuit Switched    -   CSAR Cloud Service Archive    -   CSI Channel-State Information    -   CSI-IM CSI Interference Measurement    -   CSI-RS CSI Reference Signal    -   CSI-RSRP CSI reference signal received power    -   CSI-RSRQ CSI reference signal received quality    -   CSI-SINR CSI signal-to-noise and interference ratio    -   CSMA Carrier Sense Multiple Access    -   CSMA/CA CSMA with collision avoidance    -   CSS Common Search Space, Cell-specific Search Space    -   CTS Clear-to-Send    -   CW Codeword    -   CWS Contention Window Size    -   D2D Device-to-Device    -   DC Dual Connectivity, Direct Current    -   DCI Downlink Control Information    -   DF Deployment Flavour    -   DL Downlink    -   DMTF Distributed Management Task Force    -   DPDK Data Plane Development Kit    -   DM-RS, DMRS Demodulation Reference Signal    -   DN Data network    -   DRB Data Radio Bearer    -   DRS Discovery Reference Signal    -   DRX Discontinuous Reception    -   DSL Domain Specific Language. Digital Subscriber Line    -   DSLAM DSL Access Multiplexer    -   DwPTS Downlink Pilot Time Slot    -   E-LAN Ethernet Local Area Network    -   E2E End-to-End    -   ECCA extended clear channel assessment, extended CCA    -   ECCE Enhanced Control Channel Element, Enhanced CCE    -   ED Energy Detection    -   EDGE Enhanced Datarates for GSM Evolution (GSM Evolution)    -   EGMF Exposure Governance Management Function    -   EGPRS Enhanced GPRS    -   EIR Equipment Identity Register    -   eLAA enhanced Licensed Assisted Access, enhanced LAA    -   EM Element Manager    -   eMBB Enhanced Mobile Broadband    -   EMS Element Management System    -   eNB evolved NodeB, E-UTRAN Node B    -   EN-DC E-UTRA-NR Dual Connectivity    -   EPC Evolved Packet Core    -   EPDCCH enhanced PDCCH, enhanced Physical Downlink Control Cannel    -   EPRE Energy per resource element    -   EPS Evolved Packet System    -   EREG enhanced REG, enhanced resource element groups    -   ETSI European Telecommunications Standards Institute    -   ETWS Earthquake and Tsunami Warning System    -   eUICC embedded UICC, embedded Universal Integrated Circuit Card    -   E-UTRA Evolved UTRA    -   E-UTRAN Evolved UTRAN    -   EV2X Enhanced V2X    -   F1AP F1 Application Protocol    -   F1-C F1 Control plane interface    -   F1-U F1 User plane interface    -   FACCH Fast Associated Control CHannel    -   FACCH/F Fast Associated Control Channel/Full rate    -   FACCH/H Fast Associated Control Channel/Half rate    -   FACH Forward Access Channel    -   FAUSCH Fast Uplink Signalling Channel    -   FB Functional Block    -   FBI Feedback Information    -   FCC Federal Communications Commission    -   FCCH Frequency Correction CHannel    -   FDD Frequency Division Duplex    -   FDM Frequency Division Multiplex    -   FDMA Frequency Division Multiple Access    -   FE Front End    -   FEC Forward Error Correction    -   FFS For Further Study    -   FFT Fast Fourier Transformation    -   feLAA further enhanced Licensed Assisted Access, further        enhanced LAA    -   FN Frame Number    -   FPGA Field-Programmable Gate Array    -   FR Frequency Range    -   G-RNTI GERAN Radio Network Temporary Identity    -   GERAN GSM EDGE RAN, GSM EDGE Radio Access Network    -   GGSN Gateway GPRS Support Node    -   GLONASS GLObal'naya NAvigatsionnaya Sputnikovaya Sistema (Engl.:        Global Navigation Satellite System)    -   gNB Next Generation NodeB    -   gNB-CU gNB-centralized unit, Next Generation NodeB centralized        unit    -   gNB-DU gNB-distributed unit, Next Generation NodeB distributed        unit    -   GNSS Global Navigation Satellite System    -   GPRS General Packet Radio Service    -   GSM Global System for Mobile Communications, Groupe Special        Mobile    -   GTP GPRS Tunneling Protocol    -   GTP-U GPRS Tunnelling Protocol for User Plane    -   GTS Go To Sleep Signal (related to WUS)    -   GUMMEI Globally Unique MME Identifier    -   GUTI Globally Unique Temporary UE Identity    -   HARQ Hybrid ARQ, Hybrid Automatic Repeat Request    -   HANDO, HO Handover    -   HFN HyperFrame Number    -   HHO Hard Handover    -   HLR Home Location Register    -   HN Home Network    -   HO Handover    -   HPLMN Home Public Land Mobile Network    -   HSDPA High Speed Downlink Packet Access    -   HSN Hopping Sequence Number    -   HSPA High Speed Packet Access    -   HSS Home Subscriber Server    -   HSUPA High Speed Uplink Packet Access    -   HTTP Hyper Text Transfer Protocol    -   HTTPS Hyper Text Transfer Protocol Secure (https is http/1.1        over SSL, e.g. port 443)    -   I-Block Information Block    -   ICCID Integrated Circuit Card Identification    -   IAB Integrated Access and Backhaul    -   ICIC Inter-Cell Interference Coordination    -   ID Identity, identifier    -   IDFT Inverse Discrete Fourier Transform    -   IE Information element    -   IBE In-Band Emission    -   IEEE Institute of Electrical and Electronics Engineers    -   IEI Information Element Identifier    -   IEIDL Information Element Identifier Data Length    -   IETF Internet Engineering Task Force    -   IF Infrastructure    -   IM Interference Measurement, Intermodulation, IP Multimedia    -   IMC IMS Credentials    -   IMEI International Mobile Equipment Identity    -   IMGI International mobile group identity    -   IMPI IP Multimedia Private Identity    -   IMPU IP Multimedia PUblic identity    -   IMS IP Multimedia Subsystem    -   IMSI International Mobile Subscriber Identity    -   IoT Internet of Things    -   IP Internet Protocol    -   Ipsec IP Security, Internet Protocol Security    -   IP-CAN IP-Connectivity Access Network    -   IP-M IP Multicast    -   IPv4 Internet Protocol Version 4    -   IPv6 Internet Protocol Version 6    -   IR Infrared    -   IS In Sync    -   IRP Integration Reference Point    -   ISDN Integrated Services Digital Network    -   ISIM IM Services Identity Module    -   ISO International Organisation for Standardisation    -   ISP Internet Service Provider    -   IWF Interworking-Function    -   I-WLAN Interworking WLAN    -   K Constraint length of the convolutional code, USIM Individual        key    -   kB Kilobyte (1000 bytes)    -   kbps kilo-bits per second    -   Kc Ciphering key    -   Ki Individual subscriber authentication key    -   KPI Key Performance Indicator    -   KQI Key Quality Indicator    -   KSI Key Set Identifier    -   ksps kilo-symbols per second    -   KVM Kernel Virtual Machine    -   L1 Layer 1 (physical layer)    -   L1-RSRP Layer 1 reference signal received power    -   L2 Layer 2 (data link layer)    -   L3 Layer 3 (network layer)    -   LAA Licensed Assisted Access    -   LAN Local Area Network    -   LBT Listen Before Talk    -   LCM LifeCycle Management    -   LCR Low Chip Rate    -   LCS Location Services    -   LCID Logical Channel ID    -   LI Layer Indicator    -   LLC Logical Link Control, Low Layer Compatibility    -   LPLMN Local PLMN    -   LPP LTE Positioning Protocol    -   LSB Least Significant Bit    -   LTE Long Term Evolution    -   LWA LTE-WLAN aggregation    -   LWIP LTE/WLAN Radio Level Integration with IPsec Tunnel    -   LTE Long Term Evolution    -   M2M Machine-to-Machine    -   MAC Medium Access Control (protocol layering context)    -   MAC Message authentication code (security/encryption context)    -   MAC-A MAC used for authentication and key agreement (TSG T WG3        context)    -   MAC-I MAC used for data integrity of signalling messages (TSG T        WG3 context)    -   MANO Management and Orchestration    -   MBMS Multimedia Broadcast and Multicast Service    -   MB SFN Multimedia Broadcast multicast service Single Frequency        Network    -   MCC Mobile Country Code    -   MCG Master Cell Group    -   MCOT Maximum Channel Occupancy Time    -   MCS Modulation and coding scheme    -   MDAF Management Data Analytics Function    -   MDAS Management Data Analytics Service    -   MDT Minimization of Drive Tests    -   ME Mobile Equipment    -   MeNB master eNB    -   MER Message Error Ratio    -   MGL Measurement Gap Length    -   MGRP Measurement Gap Repetition Period    -   MIB Master Information Block, Management Information Base    -   MIMO Multiple Input Multiple Output    -   MLC Mobile Location Centre    -   MM Mobility Management    -   MME Mobility Management Entity    -   MN Master Node    -   MO Measurement Object, Mobile Originated    -   MPBCH MTC Physical Broadcast CHannel    -   MPDCCH MTC Physical Downlink Control CHannel    -   MPDSCH MTC Physical Downlink Shared CHannel    -   MPRACH MTC Physical Random Access CHannel    -   MPUSCH MTC Physical Uplink Shared Channel    -   MPLS MultiProtocol Label Switching    -   MS Mobile Station    -   MSB Most Significant Bit    -   MSC Mobile Switching Centre    -   MSI Minimum System Information, MCH Scheduling Information    -   MSID Mobile Station Identifier    -   MSIN Mobile Station Identification Number    -   MSISDN Mobile Subscriber ISDN Number    -   MT Mobile Terminated, Mobile Termination    -   MTC Machine-Type Communications    -   mMTC massive MTC, massive Machine-Type Communications    -   MU-MIMO Multi User MIMO    -   MWUS MTC wake-up signal, MTC WUS    -   NACK Negative Acknowledgement    -   NAI Network Access Identifier    -   NAS Non-Access Stratum, Non-Access Stratum layer    -   NCT Network Connectivity Topology    -   NC-JT Non-Coherent Joint Transmission    -   NEC Network Capability Exposure    -   NE-DC NR-E-UTRA Dual Connectivity    -   NEF Network Exposure Function    -   NF Network Function    -   NFP Network Forwarding Path    -   NFPD Network Forwarding Path Descriptor    -   NFV Network Functions Virtualization    -   NFVI NFV Infrastructure    -   NFVO NFV Orchestrator    -   NG Next Generation, Next Gen    -   NGEN-DC NG-RAN E-UTRA-NR Dual Connectivity    -   NM Network Manager    -   NMS Network Management System    -   N-PoP Network Point of Presence    -   NMIB, N-MIB Narrowband MIB    -   NPBCH Narrowband Physical Broadcast CHannel    -   NPDCCH Narrowband Physical Downlink Control CHannel    -   NPDSCH Narrowband Physical Downlink Shared CHannel    -   NPRACH Narrowband Physical Random Access CHannel    -   NPUSCH Narrowband Physical Uplink Shared CHannel    -   NPSS Narrowband Primary Synchronization Signal    -   NSSS Narrowband Secondary Synchronization Signal    -   NR New Radio, Neighbour Relation    -   NRF NF Repository Function    -   NRS Narrowband Reference Signal    -   NS Network Service    -   NSA Non-Standalone operation mode    -   NSD Network Service Descriptor    -   NSR Network Service Record    -   NSSAI ‘Network Slice Selection Assistance Information    -   S-NNSAI Single-NSSAI    -   NSSF Network Slice Selection Function    -   NW Network    -   NWUS Narrowband wake-up signal, Narrowband WUS    -   NZP Non-Zero Power    -   O&M Operation and Maintenance    -   ODU2 Optical channel Data Unit—type 2    -   OFDM Orthogonal Frequency Division Multiplexing    -   OFDMA Orthogonal Frequency Division Multiple Access    -   OOB Out-of-band    -   OOS Out of Sync    -   OPEX OPerating EXpense    -   OSI Other System Information    -   OSS Operations Support System    -   OTA over-the-air    -   PAPR Peak-to-Average Power Ratio    -   PAR Peak to Average Ratio    -   PBCH Physical Broadcast Channel    -   PC Power Control, Personal Computer    -   PCC Primary Component Carrier, Primary CC    -   PCell Primary Cell    -   PCI Physical Cell ID, Physical Cell Identity    -   PCEF Policy and Charging Enforcement Function    -   PCF Policy Control Function    -   PCRF Policy Control and Charging Rules Function    -   PDCP Packet Data Convergence Protocol, Packet Data Convergence        Protocol layer    -   PDCCH Physical Downlink Control Channel    -   PDCP Packet Data Convergence Protocol    -   PDN Packet Data Network, Public Data Network    -   PDSCH Physical Downlink Shared Channel    -   PDU Protocol Data Unit    -   PEI Permanent Equipment Identifiers    -   PFD Packet Flow Description    -   P-GW PDN Gateway    -   PHICH Physical hybrid-ARQ indicator channel    -   PHY Physical layer    -   PLMN Public Land Mobile Network    -   PIN Personal Identification Number    -   PM Performance Measurement    -   PMI Precoding Matrix Indicator    -   PNF Physical Network Function    -   PNFD Physical Network Function Descriptor    -   PNFR Physical Network Function Record    -   POC PTT over Cellular    -   PP, PTP Point-to-Point    -   PPP Point-to-Point Protocol    -   PRACH Physical RACH    -   PRB Physical resource block    -   PRG Physical resource block group    -   ProSe Proximity Services, Proximity-Based Service    -   PRS Positioning Reference Signal    -   PRR Packet Reception Radio    -   PS Packet Services    -   PSBCH Physical Sidelink Broadcast Channel    -   PSDCH Physical Sidelink Downlink Channel    -   PSCCH Physical Sidelink Control Channel    -   PSSCH Physical Sidelink Shared Channel    -   PSCell Primary SCell    -   PSS Primary Synchronization Signal    -   PSTN Public Switched Telephone Network    -   PT-RS Phase-tracking reference signal    -   PTT Push-to-Talk    -   PUCCH Physical Uplink Control Channel    -   PUSCH Physical Uplink Shared Channel    -   QAM Quadrature Amplitude Modulation    -   QCI QoS class of identifier    -   QCL Quasi co-location    -   QFI QoS Flow ID, QoS Flow Identifier    -   QoS Quality of Service    -   QPSK Quadrature (Quaternary) Phase Shift Keying    -   QZSS Quasi-Zenith Satellite System    -   RA-RNTI Random Access RNTI    -   RAB Radio Access Bearer, Random Access Burst    -   RACH Random Access Channel    -   RADIUS Remote Authentication Dial In User Service    -   RAN Radio Access Network    -   RAND RANDom number (used for authentication)    -   RAR Random Access Response    -   RAT Radio Access Technology    -   RAU Routing Area Update    -   RB Resource block, Radio Bearer    -   RBG Resource block group    -   REG Resource Element Group    -   Rel Release    -   REQ REQuest    -   RF Radio Frequency    -   RI Rank Indicator    -   MV Resource indicator value    -   RL Radio Link    -   RLC Radio Link Control, Radio Link Control layer    -   RLC AM RLC Acknowledged Mode    -   RLC UM RLC Unacknowledged Mode    -   RLF Radio Link Failure    -   RLM Radio Link Monitoring    -   RLM-RS Reference Signal for RLM    -   RM Registration Management    -   RMC Reference Measurement Channel    -   RMSI Remaining MSI, Remaining Minimum System Information    -   RN Relay Node    -   RNC Radio Network Controller    -   RNL Radio Network Layer    -   RNTI Radio Network Temporary Identifier    -   ROHC RObust Header Compression    -   RRC Radio Resource Control, Radio Resource Control layer    -   RRM Radio Resource Management    -   RS Reference Signal    -   RSRP Reference Signal Received Power    -   RSRQ Reference Signal Received Quality    -   RSSI Received Signal Strength Indicator    -   RSU Road Side Unit    -   RSTD Reference Signal Time difference    -   RTP Real Time Protocol    -   RTS Ready-To-Send    -   RTT Round Trip Time    -   Rx Reception, Receiving, Receiver    -   S1AP S1 Application Protocol    -   S1-MME S1 for the control plane    -   S1-U S1 for the user plane    -   S-GW Serving Gateway    -   S-RNTI SRNC Radio Network Temporary Identity    -   S-TMSI SAE Temporary Mobile Station Identifier    -   SA Standalone operation mode    -   SAE System Architecture Evolution    -   SAP Service Access Point    -   SAPD Service Access Point Descriptor    -   SAPI Service Access Point Identifier    -   SCC Secondary Component Carrier, Secondary CC    -   SCell Secondary Cell    -   SC-FDMA Single Carrier Frequency Division Multiple Access    -   SCG Secondary Cell Group    -   SCM Security Context Management    -   SCS Subcarrier Spacing    -   SCTP Stream Control Transmission Protocol    -   SDAP Service Data Adaptation Protocol, Service Data Adaptation        Protocol layer    -   SDL Supplementary Downlink    -   SDNF Structured Data Storage Network Function    -   SDP Session Description Protocol    -   SDSF Structured Data Storage Function    -   SDU Service Data Unit    -   SEAF Security Anchor Function    -   SeNB secondary eNB    -   SEPP Security Edge Protection Proxy    -   SFI Slot format indication    -   SFTD Space-Frequency Time Diversity, SFN and frame timing        difference    -   SFN System Frame Number    -   SgNB Secondary gNB    -   SGSN Serving GPRS Support Node    -   S-GW Serving Gateway    -   SI System Information    -   SI-RNTI System Information RNTI    -   SIB System Information Block    -   SIM Subscriber Identity Module    -   SIP Session Initiated Protocol    -   SiP System in Package    -   SL Sidelink    -   SLA Service Level Agreement    -   SM Session Management    -   SMF Session Management Function    -   SMS Short Message Service    -   SMSF SMS Function    -   SMTC SSB-based Measurement Timing Configuration    -   SN Secondary Node, Sequence Number    -   SoC System on Chip    -   SON Self-Organizing Network    -   SpCell Special Cell    -   SP-CSI-RNTI Semi-Persistent CSI RNTI    -   SPS Semi-Persistent Scheduling    -   SQN Sequence number    -   SR Scheduling Request    -   SRB Signalling Radio Bearer    -   SRS Sounding Reference Signal    -   SS Synchronization Signal    -   SSB Synchronization Signal Block, SS/PBCH Block    -   SSBRI SS/PBCH Block Resource Indicator, Synchronization Signal        Block Resource Indicator    -   SSC Session and Service Continuity    -   SS-RSRP Synchronization Signal based Reference Signal Received        Power    -   SS-RSRQ Synchronization Signal based Reference Signal Received        Quality    -   SS-SINR Synchronization Signal based Signal to Noise and        Interference Ratio    -   SSS Secondary Synchronization Signal    -   SSSG Search Space Set Group    -   SSSIF Search Space Set Indicator    -   SST Slice/Service Types    -   SU-MIMO Single User MIMO    -   SUL Supplementary Uplink    -   TA Timing Advance, Tracking Area    -   TAC Tracking Area Code    -   TAG Timing Advance Group    -   TAU Tracking Area Update    -   TB Transport Block    -   TBS Transport Block Size    -   TBD To Be Defined    -   TCI Transmission Configuration Indicator    -   TCP Transmission Communication Protocol    -   TDD Time Division Duplex    -   TDM Time Division Multiplexing    -   TDMA Time Division Multiple Access    -   TE Terminal Equipment    -   TEID Tunnel End Point Identifier    -   TFT Traffic Flow Template    -   TMSI Temporary Mobile Subscriber Identity    -   TNL Transport Network Layer    -   TPC Transmit Power Control    -   TPMI Transmitted Precoding Matrix Indicator    -   TR Technical Report    -   TRP, TRxP Transmission Reception Point    -   TRS Tracking Reference Signal    -   TRx Transceiver    -   TS Technical Specifications, Technical Standard    -   TTI Transmission Time Interval    -   Tx Transmission, Transmitting, Transmitter    -   U-RNTI UTRAN Radio Network Temporary Identity    -   UART Universal Asynchronous Receiver and Transmitter    -   UCI Uplink Control Information    -   UE User Equipment    -   UDM Unified Data Management    -   UDP User Datagram Protocol    -   UDSF Unstructured Data Storage Network Function    -   UICC Universal Integrated Circuit Card    -   UL Uplink    -   UM Unacknowledged Mode    -   UML Unified Modelling Language    -   UMTS Universal Mobile Telecommunications System    -   UP User Plane    -   UPF User Plane Function    -   URI Uniform Resource Identifier    -   URL Uniform Resource Locator    -   URLLC Ultra-Reliable and Low Latency    -   USB Universal Serial Bus    -   USIM Universal Subscriber Identity Module    -   USS UE-specific search space    -   UTRA UMTS Terrestrial Radio Access    -   UTRAN Universal Terrestrial Radio Access Network    -   UwPTS Uplink Pilot Time Slot    -   V2I Vehicle-to-Infrastruction    -   V2P Vehicle-to-Pedestrian    -   V2V Vehicle-to-Vehicle    -   V2X Vehicle-to-everything    -   VIM Virtualized Infrastructure Manager    -   VL Virtual Link,    -   VLAN Virtual LAN, Virtual Local Area Network    -   VM Virtual Machine    -   VNF Virtualized Network Function    -   VNFFG VNF Forwarding Graph    -   VNFFGD VNF Forwarding Graph Descriptor    -   VNFM VNF Manager    -   VoIP Voice-over-IP, Voice-over-Internet Protocol    -   VPLMN Visited Public Land Mobile Network    -   VPN Virtual Private Network    -   VRB Virtual Resource Block    -   WiMAX Worldwide Interoperability for Microwave Access    -   WLAN Wireless Local Area Network    -   WMAN Wireless Metropolitan Area Network    -   WPAN Wireless Personal Area Network    -   X2-C X2-Control plane    -   X2-U X2-User plane    -   XML eXtensible Markup Language    -   XRES EXpected user RESponse    -   XOR eXclusive OR    -   ZC Zadoff-Chu    -   ZP Zero Power

Terminology

For the purposes of the present document, the following terms anddefinitions are applicable to the examples and embodiments discussedherein.

The term “circuitry” as used herein refers to, is part of, or includeshardware components such as an electronic circuit, a logic circuit, aprocessor (shared, dedicated, or group) and/or memory (shared,dedicated, or group), an Application Specific Integrated Circuit (ASIC),a field-programmable device (FPD) (e.g., a field-programmable gate array(FPGA), a programmable logic device (PLD), a complex PLD (CPLD), ahigh-capacity PLD (HCPLD), a structured ASIC, or a programmable SoC),digital signal processors (DSPs), etc., that are configured to providethe described functionality. In some embodiments, the circuitry mayexecute one or more software or firmware programs to provide at leastsome of the described functionality. The term “circuitry” may also referto a combination of one or more hardware elements (or a combination ofcircuits used in an electrical or electronic system) with the programcode used to carry out the functionality of that program code. In theseembodiments, the combination of hardware elements and program code maybe referred to as a particular type of circuitry.

The term “processor circuitry” as used herein refers to, is part of, orincludes circuitry capable of sequentially and automatically carryingout a sequence of arithmetic or logical operations, or recording,storing, and/or transferring digital data. The term “processorcircuitry” may refer to one or more application processors, one or morebaseband processors, a physical central processing unit (CPU), asingle-core processor, a dual-core processor, a triple-core processor, aquad-core processor, and/or any other device capable of executing orotherwise operating computer-executable instructions, such as programcode, software modules, and/or functional processes. The terms“application circuitry” and/or “baseband circuitry” may be consideredsynonymous to, and may be referred to as, “processor circuitry.”

The term “interface circuitry” as used herein refers to, is part of, orincludes circuitry that enables the exchange of information between twoor more components or devices. The term “interface circuitry” may referto one or more hardware interfaces, for example, buses, I/O interfaces,peripheral component interfaces, network interface cards, and/or thelike.

The term “user equipment” or “UE” as used herein refers to a device withradio communication capabilities and may describe a remote user ofnetwork resources in a communications network. The term “user equipment”or “UE” may be considered synonymous to, and may be referred to as,client, mobile, mobile device, mobile terminal, user terminal, mobileunit, mobile station, mobile user, subscriber, user, remote station,access agent, user agent, receiver, radio equipment, reconfigurableradio equipment, reconfigurable mobile device, etc. Furthermore, theterm “user equipment” or “UE” may include any type of wireless/wireddevice or any computing device including a wireless communicationsinterface.

The term “network element” as used herein refers to physical orvirtualized equipment and/or infrastructure used to provide wired orwireless communication network services. The term “network element” maybe considered synonymous to and/or referred to as a networked computer,networking hardware, network equipment, network node, router, switch,hub, bridge, radio network controller, RAN device, RAN node, gateway,server, virtualized VNF, NFVI, and/or the like.

The term “computer system” as used herein refers to any typeinterconnected electronic devices, computer devices, or componentsthereof. Additionally, the term “computer system” and/or “system” mayrefer to various components of a computer that are communicativelycoupled with one another. Furthermore, the term “computer system” and/or“system” may refer to multiple computer devices and/or multiplecomputing systems that are communicatively coupled with one another andconfigured to share computing and/or networking resources.

The term “appliance,” “computer appliance,” or the like, as used hereinrefers to a computer device or computer system with program code (e.g.,software or firmware) that is specifically designed to provide aspecific computing resource. A “virtual appliance” is a virtual machineimage to be implemented by a hypervisor-equipped device that virtualizesor emulates a computer appliance or otherwise is dedicated to provide aspecific computing resource.

The term “resource” as used herein refers to a physical or virtualdevice, a physical or virtual component within a computing environment,and/or a physical or virtual component within a particular device, suchas computer devices, mechanical devices, memory space, processor/CPUtime, processor/CPU usage, processor and accelerator loads, hardwaretime or usage, electrical power, input/output operations, ports ornetwork sockets, channel/link allocation, throughput, memory usage,storage, network, database and applications, workload units, and/or thelike. A “hardware resource” may refer to compute, storage, and/ornetwork resources provided by physical hardware element(s). A“virtualized resource” may refer to compute, storage, and/or networkresources provided by virtualization infrastructure to an application,device, system, etc. The term “network resource” or “communicationresource” may refer to resources that are accessible by computerdevices/systems via a communications network. The term “systemresources” may refer to any kind of shared entities to provide services,and may include computing and/or network resources. System resources maybe considered as a set of coherent functions, network data objects orservices, accessible through a server where such system resources resideon a single host or multiple hosts and are clearly identifiable.

The term “channel” as used herein refers to any transmission medium,either tangible or intangible, which is used to communicate data or adata stream. The term “channel” may be synonymous with and/or equivalentto “communications channel,” “data communications channel,”“transmission channel,” “data transmission channel,” “access channel,”“data access channel,” “link,” “data link,” “carrier,” “radiofrequencycarrier,” and/or any other like term denoting a pathway or mediumthrough which data is communicated. Additionally, the term “link” asused herein refers to a connection between two devices through a RAT forthe purpose of transmitting and receiving information.

The terms “instantiate,” “instantiation,” and the like as used hereinrefers to the creation of an instance. An “instance” also refers to aconcrete occurrence of an object, which may occur, for example, duringexecution of program code.

The terms “coupled,” “communicatively coupled,” along with derivativesthereof are used herein. The term “coupled” may mean two or moreelements are in direct physical or electrical contact with one another,may mean that two or more elements indirectly contact each other butstill cooperate or interact with each other, and/or may mean that one ormore other elements are coupled or connected between the elements thatare said to be coupled with each other. The term “directly coupled” maymean that two or more elements are in direct contact with one another.The term “communicatively coupled” may mean that two or more elementsmay be in contact with one another by a means of communication includingthrough a wire or other interconnect connection, through a wirelesscommunication channel or ink, and/or the like.

The term “information element” refers to a structural element containingone or more fields. The term “field” refers to individual contents of aninformation element, or a data element that contains content.

The term “SMTC” refers to an SSB-based measurement timing configurationconfigured by SSB-MeasurementTimingConfiguration.

The term “SSB” refers to an SS/PBCH block.

The term “a “Primary Cell” refers to the MCG cell, operating on theprimary frequency, in which the UE either performs the initialconnection establishment procedure or initiates the connectionre-establishment procedure.

The term “Primary SCG Cell” refers to the SCG cell in which the UEperforms random access when performing the Reconfiguration with Syncprocedure for DC operation.

The term “Secondary Cell” refers to a cell providing additional radioresources on top of a Special Cell for a UE configured with CA.

The term “Secondary Cell Group” refers to the subset of serving cellscomprising the PSCell and zero or more secondary cells for a UEconfigured with DC.

The term “Serving Cell” refers to the primary cell for a UE inRRC_CONNECTED not configured with CA/DC there is only one serving cellcomprising of the primary cell.

The term “serving cell” or “serving cells” refers to the set of cellscomprising the Special Cell(s) and all secondary cells for a UE inRRC_CONNECTED configured with CA/. The term “Special Cell” refers to thePCell of the MCG or the PSCell of the SCG for DC operation; otherwise,the term “Special Cell” refers to the Pcell.

The invention claimed is:
 1. One or more non-transitory,computer-readable media (NTCRM) having instructions, stored thereon,that when executed cause an integrated access and backhaul (IAB) nodeto: receive route information for multiple routes between a userequipment (UE) and a core network via the IAB node; receiveconfiguration information to indicate a split of a data stream of the UEbetween the multiple routes, wherein the configuration informationindicates respective fractions of the data stream that are to be sent onrespective routes; receive data packets of the data stream; and selectone of the multiple routes for respective data packets based on theconfiguration information such that average fractions of datatransmitted via the respective routes substantially match the fractionsindicated by the configuration information.
 2. The one or more NTCRM ofclaim 1, wherein the route information includes respective routeidentifiers for individual routes of the multiple routes.
 3. The one ormore NTCRM of claim 2, wherein the configuration information indicatesthe fractions associated with the respective route identifiers.
 4. Theone or more NTCRM of claim 2, wherein the instructions, when executed,further cause the IAB node to transmit the data packets with the routeidentifier for the selected route included in the respective datapacket.
 5. The one or more NTCRM of claim 4, wherein the routeidentifier is included in a header of the respective data packet.
 6. Theone or more NTCRM of claim 1, wherein the average fractions are over apredetermined time period or number of data packets.
 7. The one or moreNTCRM of claim 1, wherein the average fractions substantially match thefractions indicated by the configuration information if they are withina threshold of the fractions or within a rounding error of thefractions.
 8. One or more non-transitory, computer-readable media(NTCRM) having instructions, stored thereon, that when executed cause anintegrated access and backhaul (IAB) node to: receive configurationinformation to indicate, for a data stream associated with a routingidentifier, fractions of the data stream that are to be sent over two ormore respective radio links; receive a data packet associated with therouting identifier; select a first radio link of the two or more radiolinks based on the configuration information; and encode the data packetfor transmission on the selected radio link such that average fractionsof data associated with the routing identifier that are transmitted viathe respective radio links substantially match the fractions indicatedby the configuration information.
 9. The one or more NTCRM of claim 8,wherein the radio links are egress radio links.
 10. The one or moreNTCRM of claim 8, wherein the average fractions are over a predeterminedtime period or number of data packets.
 11. The one or more NTCRM ofclaim 8, wherein the average fractions substantially match the fractionsindicated by the configuration information if they are within athreshold of the fractions or within a rounding error of the fractions.